Krieghoffs are such a mess its honestly hard to say if this stuff is real or not. Commercial guns with weird ranges are even more messy than the "late war" stuff.
That said, there are others in the 17000 range just like it floating around, including several apparently in Spain and France. Note the incomplete military acceptance but with military proofing. The matching magazines lack BAL2 acceptance also and the font seems consistent at least. There are also some in this range that are engraved (some are in Gibson's book I think) but I have a very low opinion of engraved guns in general.
Some suggest these are "rejects" that had a 1 added to them to segregate them to commercial sales, but I don't think so. It lacks any commercial proofing (which would absolutely be required), and after successfully completing military proof testing, the gun is basically finished unless it fails accuracy testing or something. Also, at least one duplicate pair is known: 7024 (1937) and 17024 (1936).
My own thoughts, for what little it is worth, is that if these are legit, the 17000 range may be a small export contract (possibly 1000 for Spain or Portugal) around 1936/37. The incomplete military acceptance coupled with the military style fireproof sort of lines up with some of the exports to Spain/Portugal/Romania of MG15s.