Just installed the new idler pulley. Looks and feels sweet. Came wrapped inside a Toyota/Lexus box from Midland Auto Parts, Dubai.
Pulled the tensioner pulley and the bearing in it is an NTN 6203LH (left hand?). Pretty greasy/crusty/ on the inside surface/really free spinny, so a new one there as well. Tensioner itself is well within spec, so I'm just getting a new NTN, knocking out old and tapping in new in the sheave. I'll double check in the morning when I can see better, but the pulleys on the drives seem A-OK.
The truck has 275K and I seriously think these are the original pulleys, so OEM is pretty stout in my view. Pretty easy job to do.
I love what you do for me Toyota...