Rare Replacement E/37 Luger Magazine?

[tharpo]

The placement of the E/37 stamp moved around in early 1940, so it being both at the top and at the mid-line of these bottoms is correct. See pics. I believe these bottoms with the E/37 stamps only occurred in 1940 on 122 magazines. So mostly likely Thunderbolts bottom was switched from a 122 to an fxo sometime in it's life.
Seiger, if you are referring to my magazine there is no evidence of it ever having a serial number. Furthermore, I purchased it with a holster and Luger straight from the family of the vet that brought it back so it has not been messed with post war.

Tom