Even if you give him the Sharingan then fast forward 13 years later, he could only use it for a couple of minutes before it proved to be far too taxing for his body. Giving his Sharingan here, would take him out far too quickly.
I think Gaara takes this with relative ease. Sasuke's Chidori did get through and injured Gaara but it was not enough to kill him. Since Kakashi lacks Sharingan, Gaara can simply launch spears out of his defense to pierce him there and then. Sasuke dodged them with 2T, I doubt Kakashi would be able to do so.
I give this to Gaara low-mid difference as he can use coffin or simply bury Kakashi with his sand. Kid Kakashi's speed feats are decent, but not at Lee or 2T Sasuke's level. There is nothing to suggest that he can hurt Gaara.