If its the idler bearing for the AC belt you are after, try the local industrial bearing supply house. Mine needed replacement several years ago and the local bearing supply place had it in stock, It has been working for last 200K miles or so.

Was only a few bucks and since they are a fairly small supplier it must have been a relatively common bearing.

hope this helps

1987 Raider/Silver/5speed/AC/Off road package
356K miles/owned since new/daily driver