You can also just buy buffing wheels and two flanges, and run them where your contact wheel goes, if you have that type of grinder.
You can stack a few together to make up the space if you can't find the proper flanges.
All you have to do is specify the proper arbor size for the buffing wheel when ordering.
With belts, cork belts work well too. You have to break them in for at least ten minutes by pushing a piece of steel into it as it's running, like you're profiling a blade. There's a recent thread on the subject in this forum.