One of the bearings on my little dynamo locked up today. It uses two 6201 2RS double seal bearings. Had to cut the inner one with a dremel tool. I didn't have a puller small enough to get under it. After cleanup everything went back together smoothly. Both bearings were $7.74 including tax. Pretty cheap repair. The kind I like. I guess not bad after 30 years. I doubt they have been changed before.