A/C pump

[Dug]

Anyone had to replace there a/c pump and what did it costs?
My pump had been making a loud screetching noise for a year , so i thought it was the belt. I put on a new belt and it still made the loud noise . I went to take a look recently because the noise and a/c stopped working. I noticed the belt was gone. I think the pump is seized up , but i didnt reach down and try turning the pully yet. Anyone changed theres out? And does a regular a/c pump from any 6.0 engine work? doug