I have a 1912 Luger that was taken home by a GI in WW I supposedly off a German officer he has helmet and belt buckle, there are unit makings in the inside of the grip, can anyone figure it out, they are: they last one,98.R12.4. the other are " X ed " out and left to right are : 12.T.S.3.112.108.S.7.23