Used or new? For used you have a lot of choice. As long as the crank taper is teh same the stock clutch was used on many Cat sleds up to 2004 or 2005 I think.
Latest version is the 0746-417. Lots of these brand new to be found cheap. E-bay etc. I thin it may be fixed pin though.
Look around. Should be easy to find a used 9 tower with the right taper for the crank.