Here's a refinished Mauser 'shooter' (mixed parts gun) $3,200 at Simpson's
https://simpsonltd.com/mauser-s-42-o...nce-parts-gun/
They also have an all-matching restored 1910 DWM military for $2,700. Even discounting these retail prices by 1/2, it's still more than the $1,100 I got for my corroded original Mauser. I have seen several restored military Lugers over the years on auction sites that went for well over $1,100.
While I agree that most original Lugers should be left alone, at some point if the corrosion has gone too far I think it a legitimate question: would refinish save further rapid deterioration and be the best option to preserve the pistol for the future? It depends on the pistol's condition, rarity etc. but I think the question reasonable.