The Small Sun ZY-T29 or ZY-T11 clones. I bought this one: http://www.banggood.com/CREE-XM-L-T6-1800lm-5-Modes-Zoomable-LED-Flashlight-Black-p-80813.html, but received the UltraFire, but it's the same thing. Cheap - I modded it to 3.5A, XM-L2 U2 1A on a Noctigon, with the e-switch custom firmware. The XP-11 at WallBuys.com I've also mod'ed but it's a different setup internally. Check out the T29 and T11 threads for details. The Small Suns have plastic lens reflectors unfortunately, at least at the time, but the UltraFire and Aleto's don't.
It's certainly not a simple mod - ZY-T11/ZY-T29 require to piggyback a Nanjg onto the existing driver because of the switch mounted on the stock driver. For the XP-11, the stock driver can be tossed and replaced with a Nanjg, but wiring in the e-switch can be a challenge, unless you are ok with very fine soldering.
Check post #19 here: https://budgetlightforum.com/t/-/21292