I've bought these 10T, drilliumed, aluminum jockey wheels from PBS for the last few years to use on my RDs with no problems.
They are pretty nice, with smooth rolling cartridge bearings and enough washer shims to make them fit most RDs with no problems and no significant/noticeable wear so far.
They also come in anodized black finish, but I don't see the sense in getting those as the anodizing will just ear off pretty quick on the cogs....