I copied and pasted the link to the auction from a US firearm board. They were extremely critical about this sale and it appeared some of them were present and had a chance to examine the rifle. Apparently there was a big crack in the stock that was withheld from the photos and the item description....The other subject being discussed was whether it was a Finn capture or not. The general consensus was that it is. There was also some debate if a marking behind the trigger guard was a possible German waffenamt.
I was going to post a link to the discussion, but it appears it has been taken down.
Brookwood
I saw that too... It might be a German captured one. The mark looks well worn. They did use them so I guess it's possible.