Hey Mark, super nice find!! Congratulations!!
As Bob said the 122, E/37 Magazine is certainly proper for your new beauty. While these have a center pin magazine bottom, they are not stamped fxo!! Some of the last 41, Code 42 Lugers may have had the "fxo" numbered bottom magazines, the N-Block would most probably have the 122 numbered bottoms!
BTW, did I tell you how happy I am for you!!
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