Tony

If it's a young tree and still dormant I'd go ahead and repot it but go easy on the root pruning. If it's leafed out already or you don't want to chance it, there is another option. Get a large grow pot, say 5 times bigger than the rootball and fill with coarse sand. Take the rootball undisturbed and put it in the pot making sure it has sand underneath it and around the sides. That will allow the roots to drain in all directions. I have used this method in a pinch to keep trees over til the proper repotting time.

Tony