John Henson isn't available but Larry Sanders could probably be had for a box of peanuts at this point thanks to his ridiculously stupid contract and Henson's emergence as one of the few good things on a terrible Bucks team.. Even though Sanders is a crazy person, he'd give us another young piece with potential for growth. Additionally Cuz has already said he enjoyed being paired with Sanders when they were playing together with team USA. If we were feeling really frisky, we could make an attempt at Chandler but the Knicks are delusional so that's not gonna happen.
Now personally, I'd avoid even being in the same state as Sanders but if we were really serious about trying to make a push for the playoffs this season, he'd probably be the defensive big to target for now. The problem is getting the pieces together to make an offer.
As for defensive SGs, Thabo is most definitely off the table. Ideally, you'd want a Jimmy Butler in there, a young gun who is still capable of growing with your core but Chicago has pretty much made it clear he's a key part of their future. If we were making a pass at Tyson Chandler, we could potentially try to get Shumpert as part of the package. The problem is finding a way to make the deal tenable for both sides (i.e. "No, you can't have Cuz).
Of course, if we really going to go balls to the wall, we could try to assemble a package that would somehow net us Rondo and Faverani from Boston while somehow keeping Demarcus, Rudy, and IT to form a potent big 4 (Cuz, Rondo, Gay, with IT off the bench). Losing IT wouldn't really be all that bad in that scenario either. Really at that point, it wouldn't really matter who we had at the 2 position as long as he could shoot the spot-up shot and defend at a decent clip. Another slightly-less-crazy option would be a trade with the Rockets that would bring in Asik and an old friend in Francisco Garcia, who is able to both hit the three ball and defend but I'm not all that sure what we could possibly offer them that they'd want.