GECO DSM's
Yes Joe Geco had several locations where their trademark products were made. I have seen many of those old catalogs and prospectus you refer to. They also handled ALOT of products made by other firms including complete firearms and other hunting, sporting gear. And as in the case of Sears and Roebuck contracted other firms to produce products with their trademark on them.
No doubt they made the other variation of DSM at their own production base. That is a different variation. But the earlier variation as depicted here IMO was not. It clearly was made on the same line that the Waffenstadt Suhl was. Put them side by side, take them apart, compare.
To me this is a further indication that Sauer assembled these and the Waffen Stadht Suhl. Stock finish, markings, metal finish, font, the double S logo, all mirror those GECO logo'd but Sauer produced side by side shotguns.
Hard to set aside what we think we know and work outside the box. I struggle with that all the time.
Look at the guns, let them talk to you.
Without documents, I realize we will always have a hung jury on this.
Some amazing things have been discovered in the Suhl Archives, I have no doubts that significant efforts have been made there to view and extract information, I think it is very possible that more evidence may be there.
It is also possible (indeed likely) that there are alot of documents that were lost in the caos, particularly after we handed the area off to the Russians.