Interesting. However,, I doubt a prototype. I think counterfeit. Look at the head of the eagle, as well as the neck.
There have been counterfeits made of several, and with the right type of machine, many look almost perfect. I good friend of mine, his wife, had a machine to do patches. Very interesting to watch her turn out a few things.
But,, if your source is solid,,, then, DRATS,, I have another one to hunt for.
(I'll watch my mail!)