You need to post pics of the crack before you scrap a good hull. If it goes all the way around it could be the parting line between the hull bottom and the deck cap. It might just require a new rub rail to be good as new.
Now, if you find the hull is not usable and go forward with another boat... just about any jet you will find can be adapted to any engine you have currently or wish to install with just a few pieces.
Again, post pics of the next hull and hardware so we can help you evaluate it and hopefully keep you from wasting your money.