Depending on your belt tensioners configuration you might be able to pull the pulley and put some bearing grease on the bushing and bolt to get you by. Mine did the same thing a couple of weeks ago. You can replace the bearings but Toyota will only sell you the entire pulley. (Atleast for my year model) If you just need the bearing do a local search for a bearing company. The bearing should cost about $15 while the pulley is about $75.

'86 Toyo 4wd
'04 600RR