DCS World OpenBeta\Mods\aircraft\AH-64D\Cockpit\Textures
For example: Pilot_AH64_FP_jacket
However, I have not figured out yet how to call these files via the description.lua for I could not find any entry when loading the cockpit.edm nor the apache's edm via the model viewer. There is one for the helmet too. These were the only edms I could find.