Great info, Louis, thank you. I think you and I and Lancaster are all pretty much of the same mind, that this is a surplus Mauser, rebarrelled post-war to 7.62 NATO. If the guy does finally start responding and I can negotiate a deal, I'm counting on it being a fairly common model, which will make parts simpler. The only thing I can really make out in the blurry pic of the front ring is the byf code, which I believe stands for a Kar98 Oberndorf, so I'm hopeful.