I had the same problem as you! I gave up in the end and just got it from Ford. £100.

Pully attached to the Aluminum arm/spring.
I was told they didn't do just the pully. I think someone on here had the same problem and changed the bearing! But my pully was past that!!
Search posts for "air con" "aircon" under MK5. you may find his posts about the bearing. I hope!!
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