Were you in WWII, especially at a time when the German armies were being pushed back to the fatherland? They didn't have much time to get bored.
I don't know about gun collecting in
Germany
, but fakes abound in the U.S. It is best to look at any unusual pistol as being a fake and see if you can justify it being an original and correct specimen. Jesse James mother capitalized on souvenir pistols when she sold numerous pistols as having belonged to her dead son Jesse. As soon as she sold out one batch she would buy another batch for those wanting one of Jesse's pistols. They weren't necessarily fake, but never belonged to Jesse James either.
There is absolutely no way to prove that the pistol in question is anything but someone's attempt to add a story to an otherwise altered pistol.
An uncle was a sergeant in the 1269th ECB in Europe during WWII, and a PFC in his squad was originally named George I. Bernheimer, but changed his name to Bernay when he joined the army in case he were captured. PFC Bernay was killed in an ambush on December 7, 1944 near Moulinet,
France
.