I was bidding on that one too but the price got out of hand for me.
There looks to be major rust pitting on the bolt shroud and even worse on the front sight and barrel.
It is a very special rifle, but putting it right would have been a major project.
Perhaps it went to the floor where somebody got a really good look at the bore and overall condition and felt it was worth the effort.
There was another Oberndorf Mauser I liked in the auction. Lot #784.
A late 8x57 TypeB, double square bridge, sold with another unusual Mauser with British proofs.