The seller says the following about it on website:

"The rifle’s condition is truly remarkable, with no signs of wear on the metal or wood, preserving its original factory finish and crisp markings in pristine state. ---- The walnut stock’s rich grain and the sleek, unmarred metalwork highlight Mauser’s attention to detail during the early 1930s, a period when the company catered to discerning hunters and collectors."

The above words clearly represent it as original, including the stock. Except for the modern pad, right?

It's a re-stock, and done to a quality level well below that accomplished by the Mauser factory back in the day. That stock is nothing like close to a Type B or even Type A stock. The style is all wrong (looks like someone ripped a Slee). With that little drop and no scope most shooters would find it a real bastard to shoot with the irons unless a very, very short neck. The checkering is not close to an Oberndorf Mauser and is poory executed to boot. The crossbolts are poorly fitted and look like US-made Talley; definitely not vintage Mauser. Looking closely the sanding is poorly done and the pores aren't filled. I reckon an experienced eye looking at the inlet would be revealing. Look at the forend, it is not inlet to half way and appears in the photo to have a definite fall away from centreline towards the tip. I'd say the metalwork has been re-blued. Hell - look at the bolt face photo! Unfired, as they claim? "adherence to Oberndorf’s stringent standards" - absolutely not.

That stock cannot even be represented as a well done custom stock. It's a handle, nothing more, and detracts from the value of the rifle.