Kathal:
Haven't a clue on the cypher. I don't think it is a Merkel and if it doesn't have the "GM" cypher on the left side of the rear barrel lug and on the frame, I have serious reservations about it being a Merkel. Let me ask a few folks on the shiny tubes. The engraving might be by Franz Keller(?), but let me compare it.

Kind Regards,

Raimey
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