David:
Yes indeed it does look German in this pic and what looks to be screws along with the hallmarks of a frame from Suhl. The proofmarks would tell the tale. Does it have sling swivels? Possibly someone wanted an Anson type forend. Erhardt's type steel was the stock for the tubes. More than likely there's a maker's mark foward of the flats, usually on the left tube or could be on the right tube near the forend lug.
Sömmerda, Thüringen is the location RM&M was based. Either the example was made there or there was a firearms merchant there.
ö - (alt 148)
ü - (alt 129)
Kind Regards,
Raimey
rse