First things first, identify the cartridge.
That is most important.

The information below was posted by Pete over on the DoubleGunShop site. (also, here is the thread.)
Pete is super-great guy and a great enthusiast.
Here are the Sauer cartridges...

6.5x48R Sauer : (GSP17)
6.5x58R Sauer : (GSP18)
6.5x65R Sauer : (GSP19)
8x48R Sauer : (GSP21)
6.5x70R Sauer : (GSP20)
8x58R Sauer : (GSP22)
9x58R Sauer : (GSP24)
9.3x72R Sauer : (GSP25)
10x50R Sauer : (GSP26)

You need to know for double damn sure what the gun is chambered for.
The price is much too high if you have to guess.

Email the guy and find out what makes him think it's the 6.5x48r
Have him send you a complete set of proof-mark photographs.

My rifle in 6.5x53r is a sweet little Jeffery Mannlicher sporter. I haven't hunted with it much yet besides coyote here on the ranch.

Cheers
Tinker