It has been somewhere for something, I doubt US&S put that A9 84 stamp on it.
I am seeing posts on the various boards, people are getting the plain vanilla refurb mixmasters, perfectly authentic USGI even though not factory original, and looking for same make parts to render them "correct." I have heard of that in the Garand field, but the established 1911 collectors look down their noses at anything more than rounding up the right grips.