Seeking information on stock markings on newly acquired Winchester M1917
I recently purchased a Winchester M1917 that has several markings on the stock that I cannot find any information on. It has a boxed SAA that I believe is for the San Antonio Arsenal. There is a boxed S and a boxed 3GM-K that I cannot find the meaning of. I assume more arsenal rebuilds? On the very front of the stock there is a very strong "J" stamp. Everything that I can find says that there should be either an "E", "R" or "W" in this location. Inside of the stock there is an "X" stamped. Any help on deciphering these would be greatly appreciated.