When your on our home page, there are some advertisers for Seadoo parts. Have you tried with any of these sites yet?
I woudn't trust buying this item from ebay, since it is electronic and you never know what your getting.
Your right, our sponsers don't go that far back, but guess what? I found one for you! In my search, I ran across your engine size. You state it's a 650cc when the only engine size I could find for that year and model was the 587cc. Anyway, your CDI/MPEM will cost you about $147.00 and you can find it at this web link http://www.parkeryamaha.com/index.asp?PageAction=VIEWPROD&ProdID=26268. I hope this works out for you. That's a pretty good price for a MPEM.
BTW, the CDI (capacitor discharge ignition) is built into the MPEM (multi purpose electornic module). I hope they still have one left for you.
Go check it out and let me know if they were able to hook you up!...