power steering

ok so today my power steering started whining really bad and eventually stopped working. I looked under the hood and it looks like the pully on it (which for some reason is made out of plastic!! cheap ass GM) is tilted out of line, the belt is still on but it seems like the pully on hte steering pump is stripped out or broken or something because it is still being spun by the belt but when i turn the wheel it starts squealing like crazy.

I am a poor college student and need the cheapest fix possible, so can the pully part just be replaced or will i have to get an entire new pump. it never had a problem with the pump or even a squeal before this, so im guessing the rest of the pump is still good? anybody have any suggestions?

ps-- 94 gt 3.1 v6

also, as im at school i have none of my tools and nowhere to work on my car, so what would it cost to have a mechanic do a job like this?

have you taken the belt off yet. IF not, it's possible that the pump shaft failed and if you take the belt off, the pulley and shaft may fall out together. IF the pump shaft is still attached in the pump, just a pulley replacement may be necessary, which will require a trip to the dealer. The new or aftermarket reman pumps do not come with pulleys, and the dealer is the only place to get one.

thanks rich, if this were the case would i notice anything like leaking fluid or any other signs? Im pretty sure its just the pully because it looks like there is a gap between the pully and the shaft where the pully deteriorated and then must have wore itself down more and more until it stopped working.
Im gonna take the belt off today and find out for sure but im just wondering if there are any other noticable signs of pump shaft failure