I have a Rolex my Dad gave me on my 18th, used, it was his, that looks a lot like this one, but I could swear he said it was a Submariner:
I'll have to go and look now. Maybe "Oyster date GMT Master II" is the same thing? I know virtually nothing about it. I wonder how I would even know if it was real? I know he said that before he gave it to me, he had the bezel replaced and had it gone over at a watch place, so maybe it's real. I've thought about hawking it. Again, I don't wear watches.