[Herb]

M38, to further confuse things, in Costanzo's book 'Luger Proof Marks' he goes into some detail about that 'v' suffix. The 'v, w, x and y suffixes were found only on Mauser Banner Lugers. In your case, serial number 4357v falls into an identified range of 4351v to 4380v which were made in July 1937 and were for a Portugese contract of which only 350 were produced. He cites Datig's 'The Luger Book' as the source, however I havent't checked it to see where the info is. Furthermore the Erfurt Lugers without the stock lug would have been made prior to 1909. Carefully check the frame for Erfurt proofs, inside and out, as Erfurt liked to stamp nearly everything including the grip screws. Their stamp is comprised of a letter with a 'cap' over it, they look sort of like a tiny grip screw from the side in appearance. My guess is you have a parts gun that has been refinished with the addition of the Erfurt toggle train, and has been renumbered to match. I know that this is not good news, and it may not be accurate information but it is what I have available.