I'm running a de-domed XP-G2 at 3.85A, but only getting 125 kcd, though I think that # is low because measuring at only 4.3 meters. I used this XPG reflector from KD: kaidomain.com C8 XPG. XP-G2's just increase their output on copper with more amps - Match's charts show it increasing at 4 amps still, here: https://budgetlightforum.com/t/-/16621.
If your #'s are good and getting 115 kcd at 2.85A, I'm think'n that reflector is really awesome. I'm ordering two now... LED positioning and the reflector I've seen make big differences.
For AR lens, I got the AR lens from IOS and UCL from flashlightlens.com, though you may have issues with the thinness of the IOS lens - they were nuch thinner than the stock C8 lens in one C8, so didn't end up using it.