I'm not sure, but I think I paid $275 shipped for the fronts that I bought from Fast Lane and $350 shipped for the rears off a guy on Ebay. He charged me that much for the rears because he was selling the fronts and rears as a set and I didn't need the fronts, so I had to convince him with more money to break up the set. I REALLY wanted those rears.
The rears don't bolt up directly so be sure to take the brackets off your stock rears before you get rid of them and mount them on the MSP rears. I got rid of mine before I realized this, so now I have to go to a junkyard. I don't know why they don't bolt up, it's the same frame. The fronts bolt up just fine.