Well suspending my suspicions for a moment, if you were sold this as an Omega of any kind, you were the victim of a fraud, though perhaps a minor one, and should feel aggrieved. What is a shame is that if it wasn't covered in fake markings it would make for a nice cheap beater using a robust everyday AS Schild movement. As it is, it is fit for nothing more than the bin sadly. There is a fake thread on here which is worth a look, there are several on there very similar to yours, it was commonly seen back in the 60s.
