Update:
I pulled the unit. Spun 'er a few times. She seemed to indicate good bearings per Mex's stipulations. Like butter. 2 maybe 3 revolutions after a good hand spinning and dead silent.
Took it to a shop I have faith in. Said brushes are a good 80%, she's very clean both internally and externally and the bearings are in good shape.
Said the regulator trio was the problem. Didn't recommend taking my money for anything else... and I should mention... one of the mechanics is a high-hour pilot ;).
They have the part. Should be done by the end of the day or in the morning. $55.
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