There is/was the 'Keyster' kit on eBay:
But from what I read, only about 1/2 of it was usable. Maybe try searching the old board for users first hand experiences using it, I never tried it since I read quite a few negative reviews.
Parts like the gaskets and other misc wear parts I'd do what you did and just order them from an OEM retailer like Boats.net or your local dealer.
If you're trying to tune the carb, I just tried to reconcile some of the threads from the old board, but all the links don't seem to work yet...