As for Sloan assistants, obviously, the big name is Phil Johnson, Sloan's top assistant, who is a former Coach Of The Year winner. Of course, if you want to try to get Johnson, you might be better off trying to get Sloan. Tyrone Corbin isn't ready (in my opinion), and Scott Layden is more of a front-office type (as you may remember from his stint in New York).
There's a former Sloan guy out there - Gordon Chiesa - and I'm not sure where he is now. He's been a bit of a vagabond after leaving Utah. He's probably available, and is also probably ready.
But if what you're looking for is a disciplinarian, there are two of them out there. Of course, one of them, I'd be very tenative about - Reggie Theus - and the other, I wouldn't touch with a 10 foot pole - P. J. Carlesimo (or as I call him, "P.J. Car-loss-imo." I can come up with a ton of reasons that Carlossimo is a great fit - I can make a great argument - just as long as you're willing to overlook the fact that he's an awful head coach.
Are you more in need of a TEACHER than a DISCIPLINARIAN? Tim Grgrich is out there, and I think he'd be great. It's about time he got a real chance.