What To Do with a 340 engine?

you will need to post lots of pics and have lots of info e.g. size of the current pistons, if it still has the forged crank, does it have X heads, etc. If you get it checked for cracks and get the bores and crank evaluated (without getting the machine work done), you can ask more for the motor, since otherwise you would be buying a "pig in a poke", that could be worth nothing but scrap.