While I think that now, Kimimaro would be defeated by the tag team of Gaara/Lee, it doesn't really escape the fact that Orochimaru isn't on anywhere near the level of Kimimaro; he's far, far, far higher.
Don't think that I'm trying to make Orochimaru look invincible, because that's not what I'm getting at; but Orochimaru by himself would be an extremely difficult battle for Gaara/Lee because of his experience with all forms of jutsu, his overall skills, and the fact that in this scenario, Gaara and Lee have NO information on Orochimaru or his jutsu whatsoever; that, and Kimimaro is there in the mix too—he could provide -excellent- backup.
Granted that Orochimaru won't have information on Gaara/Lee, it would become apparently obvious that Lee was restricted to Taijutsu very quickly to Orochimaru, and as long as Lee didn't get close, Orochimaru wouldn't really have to worry about Lee. I firmly believe that Gaara even alone would put up a decent fight against the two of them, but even with Lee as his partner, Gaara and Lee couldn't win a fight with Orochimaru and Kimimaro.
Yes, three years ago, Kimimaro overpowered Lee (although Lee was drunk), and survived Gaara's attacks, but he died; he would've killed Gaara if not for his sickness and a little bad luck with the Laws of Motion at the time of his death. But just because Kimimaro died back then and hasn't really been able to get stronger like Lee and Gaara doesn't mean he's just a wimp and would get smashed by Gaara or Lee in one hit; it just doesn't work like that.
So all in all, Orochimaru and Kimimaro would be victorious in the end. That's my opinion.