Bob, in my experience with spring starters heat is the thing that usually ruins the plastic springs. Two seasons was about the normal lifespan for the bearings in my planes. I would guess that, in your area, there is a bearing supply. Take the bearing down to them and have them match the number. When you have more trouble with it, change it out. It's not too hard to get it out of the sleeve.

I no longer have any engines that use spring starters. Thank goodness.