High performance 2-stroke engines , like those found in PWCs, are very prone to failure. Spinning around at 6K rpm will bring nothing but trouble. PWCs are not like boats; a well maintained boat engine may last the life of the hull ...... a PWC w/ 2-stroke will almost certainly have a major engine failure within three years (and thats even if you're nice to it AND lucky!).
Unless you've trashed the crank/rods, its probably very much repairable. But, the cause of the failure
MUST be determined, or you'll just be wasting your money. Improper fuel mixture, bad seals, cooling problems will all kill an engine in just a few seconds. What were the symptoms when it died ..... does it even start anymore??
I own two 1200cc jetskiis. (stay calm, they don't go on the lake ... way too rough) I blow at least one engine a year. But, I admit that I beat the living life out of them. I'm an adrenaline junkie, and those puppies lead a tough life. But, my garage is tooled up for full service; and I keep a spare engine ready to roll & can swap it out in just a few hours. If you want to play, you gotta pay!
Find a reputable independant motor-sports repair shop ..... they'll know what to do. These guys repair engines for a living .... and its not a big deal for them to replace a cylinder & piston. It might cost you $600, but that's a whole lot better than a new engine. By far, the major portion of the labor charge is removing the engine from the hull. So, if you don't have to replace the main bearings, seals, or crank assembly, you'll be way ahead of the game.
Check out
www.sbtontheweb.com. I've never used them, but I hear they have a good reputation; and a killer no fault warranty on their engines. Many repair shops will install SBT engines, if the owners are not inclined to do so themselves. If you want to make the two hour trip, I can recommend a shop in Billerica, MA., who is well versed with SBT engines.