Curious.
I don't recognize this as an Omega movement. I bet if you get a shot of the inside of the case back you will get more info.
I vote outright forgery.
I find amazing the amount of effort to fake this watch. Router-out the Seikosha name on the movement, carve the Omega symbol, then get dial reprinted. Quite an effort.
Im new to this but i also find it strange to redo a seiko, its a nice watch in it selfe. But of course, if you can fool one that it is a omega there might be better money...