any yamaha dealer should be able to help you out, i had to replace bushings for the pole on the old SN, 91' as well, went into dealer, took a bit to find the right place to look..i dont wanna call it micro-fiche but ya..the parts page..lol
eventually we found the proper page with part #'s and it was ordered.. forget the name of the place, was in penticton..
but as the guy told me.. it's a yamaha, i'm a yamaha dealer..if they make it i can get it.
good luck.
edit...found it, try this
Penticton Yamaha & Marine ltd.
124 south beach drive, penticton, BC
250-492-8300
just a heads up this was almost 4 yrs ago but it wont hurt to call them I'm sure they'll have it shipped to you instead of store.
and just to add they dont actually carry PWC's i just went with the its a yamaha your a yamaha dealer..and it worked lol