All you need is the drop-in, host and 2 18350 batteries. This set up sounds exactly what you are looking for, I was looking for the same. Here is a link to the host I used but you can use any p60 host.
You should be able to pick up some real diffuser film (no need to use a kitchen wrap product) locally at any architectural glass supply house but you may have to buy enough to do a few windows.
Also there is a generic version of the supfire m6- the B50T .
RMM does ship internationally, request a quote.
3400s will give you a longer runtime but eit her of the Samsung 20r or newer 25 rs have less resistance and will give you higher amperage (brighter light) for shorter periods of time on the only complaint i have about the small sun is the tail switch won’t last too long other than that it is my favorite light and yes relic does ship internationally and does superb work as fast batteries you could try RMM.
The M6 seems like the best light to fit your list of requirements. Uses 3 XM-L2. Very nice light. RMM sells them for a good price.
The Crelant 7G5MT is nice, I have one and its very easy to use with the side switch buts its a long not thick flashlight.
With the requirement of flood, nice and even, and your expressed desire for an MT-G2 for tint, as well as your request for a thick bodied light it seems to me that a 2D Mag Light modified for the MT-G2 in a standard incandescent reflector will suit you exactly. You should be able to do this for under $50. You could use 2 32650’s and have great run time, or sleeve the battery tube and use 26650’s and still have really good run time.
The Vinh modified P-60 with an MT-G2 is probably not the best of ideas. Too much heat generated for that format, with not enough mass to dissipate the heat. If you know you won’t run it more than a couple of minutes at a time then the heat is manageable. More than a few minutes and the light would have to be shut down to allow it to cool.
The Solarforce K3 head on an L2P is really an excellent option for you but uses the 18650 format so won’t have the thicker body you have asked for. As far as diffusion goes, you could spray clear enamel lightly on the lens and would have a nice even flood with little or no hot spot for almost no cost. Don’t have to get fancy. By using the lens you can easily change it at will, simply clean off the enamel and start over, can’t hurt the glass with solvents. A very light amount of spray would really work well, a fairly heavy amount would give no hot spot. I’m talking about visible spots of clear enamel on the glass, not a coating at all. Sprayed from maybe 2’ away, even letting it hit the lens as an overspray, is a great idea and would probably make you very happy.
Edit: No other emitter will satisfy a tint snob who has fallen in love with the MT-G2. Not the Nichia 219, not any of em. I’m one of those, I LOVE the MT-G2 color output. 
I even have one in a chopped AA MiniMag in mule configuration running 2 14250 IMR cells. 1345 out the front lumens from a sub 3” flashlight. There’s not much throw, but boy does it light up a room! And no, on high at 3A the cells don’t hold up long at all…
I have to agree with DBCstm on the MT-G2 tint. For outdoors and big light, it's my preference too.
I also agree with his light suggestion if it fits your length preference.
Thanks for the info about the Supfire M6. Somehow I had managed to never actually look at that one, and I didn’t realize RMM sells it (always a good sign) and can mod it to make it even better. It looks like he’s too busy for the next few weeks to do any modding though.
In any case, it looks like the M6 is better than the SRK and might even cost less. Personally, I’d wait until RMM has time to mod it (at least new firmware, possibly other changes too), but that’s just my preference.
I really like the MT-G2, but it’s currently still a pain to get one working in a torch.
Oh, and the P60 MT-G2 drop-in? Definitely would have heat issues. That size light has nowhere near enough heat-shedding capacity.
Absolutely - MUCH nicer than the SRK/clones. Very bright right out of the box, but you can do a resistor mod quite easily if you wish to really crank up the high. The only downside is that it has the typical 5 modes: High, Medium, Low, Strobe, SOS, Off. You have to cycle through them to get to off. However, I’ve found that I can quickly give the head a twist which cuts the current and turns the light off. It always restarts in High.
You can get it for $40 at Mountain Electronics http://www.mtnelectronics.com/opencart/index.php?route=product/product&product_id=250
It’ll cost you $50 and up to “build-your-own” MT-G2.
I decided a couple of months ago that I already have enough flashlights in my collection.
Only thing I might possibly buy is one with the new MT-G2 emitter. Well….
After reading your comments (and others) about the tint of the MT-G2 emitter I’m convinced I need one !
Only problem is, at the moment the one I’m lusting after (Solarforce S2200) costs $200 locally 
I will take a good look at the suggestions, thanks all for the feedback, you really helped me
Very good info, and now i cant decide, so much options lol!
dazed, I took some of my own advice today and rebuilt a Maglight with an MT-G2 and the BLF 17mm DD FET driver. This light also has a Western Electronics voltage monitor in it so that makes it pretty cool. 4 modes, big shallow reflector, works quite nicely. Big hot spot that softly fades into spill, will get a beamshot later tonight. Running on 2 big protected 32650’s. Also have to get it in the lightbox…
I had bought a “drop-in” with the P7 some time ago and it always only worked like in Medium, no other modes. So I pulled the SSC P7 out and built the FET driver to piggyback onto the original board as it’s large. Got all kinds of messed up when my several year old Novae protected cells tripped me up, one of the 2 I was using tripped the protection circuit and had me chasing ghosts trying to fix the light. Never had a ic trip before so I tried literally everything before I checked the cells. Go figure!
The voltage monitor has a 6 color check sequence then sits on the color that coincides with the voltage reading, shows through a fiber optic that I mounted directly above the switch. Easy to see the status of the cells by the color of that little tiny fiber optic. I have no idea why I didn’t do this long ago, the MT-G2 is awesome in this big purple MagLite. I believe it’s pulling around 3A on these cells, so it should have nearly 2 hours run time on high. I need to check the amps again, as the protection circuit tripped when I was measuring amperage to begin with. Might have to find some newer better 32650’s. Or sleeve it and put 2 26700 Moli cells in it.
Edit: This pair of Novae 32650’s is allowing 4.33A to run through. 
Edit II: Quick lumens readings, 2498 otf at start, 2263 at 30 seconds. The cells were long time rested at 4.12V (months, maybe a year since a charge cycle) Voltage monitor started blinking red at the same time it hit 30 seconds. These cells might not handle the FET driver with the MT-G2.
Cool. Sounds like a awesome light. Looking forward to beam shots.
Made a sleeve for 26700’s from PVC, the Moli green cells fit in there perfectly. At 4.18V fresh off the Efest LUC V4 charger they give 7.65A in this MagLight. That shows up as 3609 lumens at start-up, 2833 OTF at 30 seconds. The voltage monitor is showing green at the 30 second mark, down to the 3rd level.
Edit: Correction on the Voltage Monitor, it’s from Western Robotics, called a Spectrum , reads from 5V to 29.4V.
These are my standard shot, 97 yds to the red oil drum…G1X at 1600 ISO, f/5.6 wide- f/5.8 tele, 1/2 sec exposure. Wide is 28mm equivalent, tele is 112mm equivalent. This dang thing is too bright for my standard settings! I held the light out front so the monitor could be seen…
All I can say is wow!!! nicely done!!
AMAZING! wow! i will be all over this soon
Thought you might like that result dazed, I figured the Mag would do well with the MT-G2, but am still somewhat surprised at just how well it does!
Far better than the cheap drop-in from dealextreme ever did, for sure! I had thought to use a copper slug for a heat sink and recess a driver compartment in the bottom, but thought of this light with it’s faulty driver circuitry that’s been sitting around for close to 2 years (maybe more) and just so happened to have recently gotten an MT-G2 from RMM on special without having a specific build for it. Sooooo, thinking it’d be an easy swap I did it this afternoon. Not an easy swap. lol, of course. The P7 is on a very thick aluminum star and the design of that emitter has it on a quite thick base. So it was considerably taller than the MT-G2 on a Noctigon. I cut a disc out of a sheet of copper that rufusbduck sent me a little while back, then put a 20mm copper star on top of that (it had a dielectric layer under the thermal pad, sanded it down to bare copper first) so the Noctigon for the MT-G2 is on about 3mm of copper, plus the 1.5mm of the Noctigon. Close to a quarter inch of copper re-flowed to the brass pill so it should do pretty well, the pill itself is pretty massive.
I’ll see if dealextreme still has this “drop-in” and see if I can figure out what such a build would cost, minus the expensive voltage monitor ($25 for the monitor, it’s neat, but I only did that once!)
Here’s the SSC P7 pill/reflector that they now have as a DIY build. This one has no driver or emitter, less than $8. With the MT-G2 on a 20mm Noctigon for around $20, a 2D incan MagLight for around $16, and a driver needed along with some modding to build up the emitter to fit into the reflector, a light similar to what I have would be around $50.