I had a similar problem with My AC Pulley.
The bearing was shot.
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What lead me to that was i took the drive belt off so I could see if the noise was driven by the belt.
Then I got a shorter belt to bypass the ac compressor to see if it was the alternator or not.
I got the pulley off ebay and I got a denso removal tool. Total repair was 100 but took me a week of messing with it.