Some overall pictures would definitely help, but they don't need to be as high-resolution; nevertheless, going by the "M.71" in the first photo, I'd say it's one of the versions of the M1871 Mauser, built by several German arsenals, and chambered for the 43 Mauser cartridge. We'd need the barrel length to know if it's one of the carbine or rifle versions, and there should be additional marks on the receiver, showing whether it was built at Danzig, at Spandau, at Mauser, and so on.