I agree the description is even more appalling than the rifle itself... obviously a Spanish import, but this one doesn't even have its original serial number. It was serialed either by the Spaniards or the importer.
Perhaps the most amazing thing is it has several bidders and is up to over $400, assuming the bids are legit. BTW, no wartime Mauser Oberndorf is "rare, they made a lot of rifles 1915-1918, and in 1914 they made more G98's than anyone else, not a huge number, but far more than the rest. During 1914 most makers had to be redirected back to long rifles, - Danzig from the 98a to the G98, DWM had to take rifles back up, being engaged with machine guns and pistols. Only Spandau was making rifles in any number, Amberg was making trifling numbers, probably just enough to keep its skilled men at work.
The rest of his story is mostly nonsense...