Here's one I destroyed earlier. A nice original 1950s full coat. left on a hanger by a window and untouched for at least 30 years so nice and sun faded on one side, just enough to make it un wearable for any fashion conscious 1940s vintage clothing enthusiast £5er at a car boot sale.Mouton/beaver used on collars of original G1s etc is simply sheepskin that has had the GHD hair straighteners on it. Why not find an old 40-50s ladies coat cheap and chop it up for a nice collar with a bit of wear to it.
Cheers, J.