Pick up a rolex caseback set from amazon for $30 and open the back and compare the movement to pictures of a gen. The only movement that will look close beyond some decorated bridges and rotor is the SA3135 and that has tells. From the craptastic picture, one thing I can point out is I don't see any black hole effect on the cyclops. Pretty much everything else is so blurred that it is impossible to point out faults. There is also no space between the 300m which, while can be gen, is not as common as the 300 m. Tell your friend to send you a head on picture of the dial that is actually clear. Also, why would you want a GMT master bracelet on a submariner? You are looking at over $1k to get a correct bracelet. This should be reason enough to pass.
here's one of many articles discussing the Rolex black hole...
https://forum.replica-watch.info/vb/showthread.php/344470-explanation-of-Black-Hole-effect
https://forum.replica-watch.info/vb/showthread.php/172366-TC-crystal-vs-Gen
here's one of many articles discussing the Rolex black hole...
https://forum.replica-watch.info/vb/showthread.php/344470-explanation-of-Black-Hole-effect
https://forum.replica-watch.info/vb/showthread.php/172366-TC-crystal-vs-Gen