Let him know you're interested in the seats because yours just doesn't/didn't have them. Don't tell him yours were stolen. Be friendly and try to connect on FB so you can stalk and try to find mutual connections for more positive ID'ing. Plan to meet on a day that he would be at home. You can get an idea of what he has going on by you having "schedule conflicts" to prompt him to divulge some details of his schedule as y'all try to coordinate. Chances are that he will not want you to meet at his house. You want him to be leaving his house to meet you and you're hoping he'd head back home afterward because he's likely to wanna meet conveniently close to his place- maybe a corner store he frequents. Bring a friend and meet up in a different vehicle than your Escalade. Preferably in a common, non-custom vehicle that blends in. You and your friend case this mofo- Take note of his vehicle, license plate, tattoos, wedding band... anything you can do to ID him. Either buy them back or don't ("No, thanks. They're not the color I need for mine", etc.). Take your time loading them, BS with your friend and you both appear casual and distracted elsewhere as the seller drives away, but don't lose sight. Trail him from a comfortable distance and try to pin down where he lives.
Don't pass by his house- too risky. Once you get all the info you can, come back here and PM
@Galante and he can have one of his cronies whack the dirtbag.
Problem solved and you may end up with a garage full of stolen seats or other property that can be returned to their rightful owners.