(2) Ask him.
Just tell him you find him attractive and you know he's got complex feelings regarding his ex, but you're hoping that if he gets to a point where he'd consider moving on and you're still available, that he would consider you. See how he responds. Even if he says he needs more time, once you've told him, that Si isn't going to forget... it might even get his moving-on wheels turning. It's the same answer as the first question, really. Be genuine in telling him you're interested in him, and kind in giving him the emotional time he needs to move on, without putting pressure on him to be ready to fulfill your desire.
I know it's so much easier to stay outside Schrodinger's box... but you won't get a real answer if you don't let him know.
(- in LTR with ISFJ)