Do you know the caliber? It does look a lot like the Maschinenpistole, but the handle is more perpendicular and the stock more slim and long.
Edit: Okay, it really looks like an MP 38.
http://www.google.com/search?tbm=isch&hl...682&q=mp38
Edit2: And according to this article, the MP 38 was used in the Spanish Civil War.
Edit: Okay, it really looks like an MP 38.
http://www.google.com/search?tbm=isch&hl...682&q=mp38
Edit2: And according to this article, the MP 38 was used in the Spanish Civil War.