The single 2x18650 tube probably doesn;t fit the C8 (but the seller was unable to measure the thread distance, so I do not know for sure)
I’ve ordered, received and modded the one from Tmart.
It has a FET driver (17mm & 20/26/27mm single-sided DD/FET driver release: A17DD-SO8 / A20DD-SO8 / etc) and a XHP-70 LED.
the sinkpad required a bit of filing to make it fit, both because it was too big to fit in the pill and because it was covering the holes for the wires.
It is working now but I am not totally satisfied. I’ve ordered a milli-ohm meter (Half Ohm - milliohm adapter - Projects of Jaanus Kalde) and am planning to reduce resistance as much as possible.
I also have to find a way to secure the star to the pill(is now pushed in by the reflector) either by screws or I have to order some heat conducting adhesive (any ideas on this?).