found the bearing. it is a common part. got it at the local auto parts store. I paid $13 for it. I could have ordered one for 5 plus shipping, but it was worth the extra few bucks to have it right away. plus, it is a Federal-Mogul bearing with steel seals, so I know it is good.
Are tracks directional? I have not given the new one a good for look for arrows yet, but if I could run it opposite the direction it has been worn in, I figure it will grip better.