If you have a newer bow that uses the Flanged bearings the specs are below.
If your bow has the earlier bearings they are the same specs but without the flange and the bearing part # is R3RS.

Bore dia. 0.1875"
Outer dia. 0.5000"
Flange dia. 0.5650"
Width. 0.1960"
Flange width. 0.42"

Bearing #FR3RS

You can buy bearings from Lily Bearing. Their part # is FR3zz.