Beautiful Type S. I'll defer to Don S. and others, but I don't know if the 8x64 chambering is original. Rifle appears to be an Oberndorf Type S in 8x57 that was rebarreled by Brenneke. My understanding is that only a few original Mauser Type B sporters were made in 8x64. (There was one in the Holts auction yesterday, marked and apparently modified by the Swedish firm Widforss).

I'll be very interested to see what others have to say. It's certainly a valuable and interesting piece.