So have you pulled off the belt to verify that it was one of those pulleys?

The A/C Clutch Assembly is what you are likely hearing if it is infact the A/C Assembly. I believe you can replace those components individually, but you'll likely end up spending less money in the long run by replacing the entire A/C assembly instead of just the clutch and seals.

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I've had many great experiences getting great parts from them for great prices.

95 Avenger 2.0 - Hahn 16g, DMS 8 injector setup, UDP, Big FMIC, HKS SSQV, MSD Coil & Wires,
ZEX Nitrous System, QTP Cut Out, Mandrel 2.5" Exhaust with cat delete, MP 60mm TB...and tons of Carbon Fiber