I am not a Mauser guy, I have nothing against them, I just know little about them, except original ones with intact marking go for a hefty price. If you do find one, prepare to pay out of every orifice for it. If you want a decent one, go for a Russian Capture one. They are arsenal refurbished by the Russians for use in East Germany and can be found in better shape then an "original" one. Only difference is they are "Forced Matched" meaning serials have been penned on some parts and re-serialized to match other parts, and the swastikas have been penned.
Google P&S Militaria, they have literally dozens of RC K98's. And from what I hear, they guy is a real honest guy who can pick a nice one out if you ask him to. Ellwood Epps also gets the occasional one in, they have a link above.