I seem to recall assembling the whole heavy duty kit for about $170. Make sure you get static rope, too. My kayak version was about $40-50 for just the biners, prussiks, webbing and rollers with planning on using throw bags for rope.
Also, throw the whole kit into a watershed that's strapped to one end of your raft, just so it is easily accessible when the boat is black side up. I found the Ocoee too small and upgraded to the Chattooga.