Take the bushings to a place that sells bearings. I have new bushings that have oilite in them. Not sure what that is, but that what the supply house said. They can measure them up and get what you need. I found that they were not the same, so I took them back, and they reordered. I wanted to try to put bearings in place of the bushings, but it looks that it would remove too much metal in the axel holders, as I call them rockers. Not sure what the correct name of them are.
Richard