I'm inclined to tell you that it's real - but what it is I can't say. It has the correct proofs for a commercial proofed rifle assembled (or proofed) in Oct. 1944. Some of these late war commercials are really strange, this one included. I'd say you got a good one, my opinion. A good late war commercial that is...now what they were for is not known, but it was proofed in Zella-Mehlis.
I suspect these rifles were made for local defence/ Volkssturm, but that is speculation on my part.