It's a good price since you don't have to pay for a core. Nice thing about the Merc engines is that they are self contained. I know that is missing a few things... but you can basically put a fuel line on them, and 12v... and they will run.
Tim:
I haven't seen a twin sportjet. BUT... I'm sure it exists somewhere. I know the computer can be set up as Port, Starboard, or single.