Go ahead and get a used jrsc kit but check and see if all the idler pulleys are spinning freely. If the blower has a lot of miles on it, I would be concern about the old bearings in the blower. My friend bought a used jrsc kit and he had to get the blower rebuilt because of the f'ed up bearings:
http://www.imagestation.com/album/?id=4286411017
You can rebuild the blower itself if you encounter these problems
http://preludeonline.com/showthread....ght=oil+blower