Yup, just the pulley for this fix. The stethoscope clearly showed the pulley bearings as the noise source, otherwise I'd have replaced the whole tensioner.

Interestingly, the Toyota pulley has two separate bearing assemblies pressed into it. The Gates replacement has only one, longer bearing assembly. Seems to put more bearing surface area than the factory design. Whether the bearing components are same/better/lower quality relative to the Toyota part is unknowable...but the Gates pulley has a lifetime guarantee.

Changing the tensioner is a bear. Have to remove the AC compressor to get to the tensioner bracket. And probably have to remove the alternator to get the AC compressor moved. Unbolting the AC compressor, even with the fan, radiator, alternator, and other front components removed is a PITA.