As long as you never had a wfo belt fly apart the crank should be is good shape. Come down to how well you store it in off season. As far as pistons I would think a compression test should be able to tell you the story. Good oil and well maintained should be able to put more than 3000 on it. Have not really heard many 800 letting go. I had an 02 800 that I sold this year that ran strong every year. It had 2600 miles on when I sold it. I would think you could still run it with piece of mine.