It's 7/73 F.u A. Helbig (brand name "Gaefler"), that is associated with cast iron crossguards, but I think the blade is not original to this dagger. Helbig etchings are very low quality, and here we can observe normal type etching, so I assume the blade belonged once to a ground Röhm dagger and whole item is a parts dagger.
Just one correction to my previous post: the SS Helbig dagger pictured in Wittmann Vol.IV is a transitional model.
