OK, so when you say Mauser, does that also mean it is a military weapon, as opposed to a civilian (commercial?) one? Also, what do the proof marks indicate?
It is in fact all matching, including the wood grips and all interior parts. I see what you're referring to in the photos about a line below the serial number. I went back and checked, and that is just some oil that sucked up some dust.
Just for fun I took it to C*b*l*s Gun Library to see what they'd offer. They said $950.00. I left without another word.
Still, though, can someone give me a ballpark so I can tell the current owner what she might expect to get? I'll understand if you don't want to speak up because you're interested in placing a bid on it! Thanks again for all y'all's help!