Gentlemen, before you think about American engravers, may I draw your attention to the fact the top of the barrel is marked with the pre-WW1 Sauer &Sohn Berlin,Germany retail shop adress. The "symbols at the top of the receiver", eagle and Crown/B are German proofmarks, so the rifle was assembled by Sauer &Sohn in Suhl, proofed there and probably engraved there too. The serial number 104664 most likely is the S&S number. Jim Cate in his book "J.P.Sauer&Sohn, Suhl" lists S&S serial number 104666. This is a .25-20 single shot built on a Winchester low-wall action too! So apparently Sauer about 1905-10 imported several Winchester actions to build German-style small-game rifles on.