Go DCS\Bazar\World\textures\Ka-50_general.zip
Edit the files "rus-helmet_ka-50", "ka-50-pilot_f" and "rus-pilot_ka-50", save them in your livery folder, add this:
{"KA-50-RUS-HELMET", DIFFUSE, "rus-helmet_ka-50", false};
{"KA-50-PILOT_F", DIFFUSE, "ka-50-pilot_f", false};
{"KA-50_RUS-PILOT", DIFFUSE, "rus-pilot_ka-50", false};
into the liveries description.lua and thats it.