in search for a driver.

I have absolutely zero experience with modding flashlights but I think this should be an easy one to start with.
I’d like to mod my aimai ak02. So I’m looking for an 18mm driver for a twisty running on a CR123 bat. I like the output how it is now, it’s pulling 0,45A. So max amps the driver should be pulling is 0,5A. Don’t need blinkies, can start in high. Would like low mid and high.
A single mode 18mm driver would also be good but you know, modes are nice to have. Running time on this light is more important than output so I’d like an efficient driver. Don’t know if I’m really PWM sensible so PWM driver might be ok but I read that they are not that efficient (or am I wrong?). In the future if it works out I probably want to use rechargeables so an overdischarge protection on the driver might be useful.
Don’t know which LED I’m gonna put in yet, I got a nichia doing nothing but probably I’ll start with the original LED.
I’m living in europe so please no American sources thank you.