There's a Mauser Forum online --
Heaps of books available on Mauser ID. Should be some ample online sources w/ photos.
Lots of Mausers were captured post-WWII, the markings "scrubbed" and they were re-issued, or warehoused. Refinish is often part of this process. I was buying these up from Big 5 Sporting Goods back when they were selling Turk Mausers for $49.99 out the door. I also found a Swede Oberndorf in a pawn shop. (Should have never sold that one!)
If the receiver crest has been scrubbed, there are probably some markings on the barrel, under the wood. The Nazi Eagle/Swastika (Waffenamp) appears on the side of the barrel, near the breech, and is often scrubbed too. What and where things have been scrubbed is part of the ID process.
My BRNO 98/22 has sight markings in Farsi (? Arabic/Turkish ?).
I have a Czech M 48 short rifle, 8mm. Big 5 sold lots of these unfired. They're warehouse refurbished I think, or unissued.
Back in 1995, Mausers were a glut on the market, cheap, not particularly collectable nor rare. The supply is probably dried up a bit -- along with the surplus 1940's Ecuadoran ammo going for about $50 a case of 1000 rds.
If you Google "Mauser" / "Mauser Markings" and start following links, you'll soon have more information than you can imagine. It's all over the place.