The buckle looks like it did not originally come with the watch, even though it is an Omega buckle.
Is it really? Genuine question as I’m not that deep into the differences, but the Omega logo looks just a bit too soft for me, the logo above the SWISS is not central, the gap before “INOX” isn’t that tiny bit larger than between the other letters, as far as I can tell from the pictures.
I might well be wrong, though - happy to be corrected. 😀
@nkhandekar the metal bite that goes through the leather band - sorry I don't have the name
"Pin", I think.