If it's really sloppy you should also consider buying or finding another used one perhaps in better shape.
If you rebuild one plan to put bearings and bushings in it to eliminate the slop in the shafts which will then help the seals last. But if it's been worn and out of adjustment for a long time it may still have play in the wheel after you've adjusted it best you can, and nothing but a different one in better shape will fix that.
Grigg
