I have one I bought from Cabela's at least 15 yrs. ago that's really neat. It's designed just like a regular coat, has the game bag on back, and giant ammo pouches on the sides, has large inside pockets, has a removable inner insulation, and it's water proof for bad weather. The water proof outer skin, and the insulation liner can both be unzipped and removed when not needed.
It was quite spendy back then, can't imagine what they run now, if anything like it is still available?
GS