Strange sub

[will2509]

Hi I just joined and am the proud owner of a rolex explorer II white face steel oyster band. However I saw a watch for sale today and went to look at it because it seemed cheap, he said it ws 3-5 yrs old and it was a blue sub with blue face and bezel gold and steel band and he wanted around $5,500 for it so seemed good value, however when I inspected the watch it had an old style body with the watch pins showing outside the main body, but the new style strap with gold showing on the inside, I told him I was unsure but it looked like a made up watch. He claimed his father was given it by a sheikh here in the middle east. The watch was immaculate to be honest and had I not read a bit about them on here I would probably have taken it. The watch came in a rolex box but no papers, was I right to walk away?
Thanks
Will