The one player that stands out here(in my opinion) is I.Thomas. He is getting minutes and is heating up. There is a grab-bag of players that merit consideration for rounding out the trio you are looking for.
Bargnani may get traded(possibly increasing his value) and is a rarity in that he can hit 3s from the center position.
Humphries, rumored to be heading to the Bobcats for Ben Gordon, would be a definate pick here if that happens.
Villanueva, now taking most of the minutes vacated by the injured A.Drummond, is certainly worth a look.
Bogut is a beast if he can stay on the court.
Bayless has taken off with Rudy Gay's offense gone, but I don't know if he'll keep up with his solid #s. I think he will, but he is not doing well so far in tonight's game.
Jeff Green is playing decent ball, but his value would most likely soar if Garnett is traded. Keep a watch on him.
If I were hard-pressed to pick 3 from this bunch without knowing specific needs, I would say Thomas(without a doubt), Bargnani, and Bayless. Lot of good options, but I would roll the dice with those 3. The trade deadline might shake a lot up, but for the time being, I choose those 3.