As far as I know they were car specific to the 86-87 regal and the 89 tta. Don't hold me to that, however. I needed one myself so I had to do some hunting about a year ago. I do recall that I could still get it from GM. The dealer was rather high, but once I had the PN gmpartsdirect had it for like $60. It comes as a complete assembly, you get the bracket that mounts to the front of the motor as well as a new pully and bearing.
I would bet the PN is over at gnttype.org in the tech section. There is a huge list of GM part number there.
Brent
