Hey what are the options?
Boat with no motor, waiting for one -
or
Boat with a slap together motor, that may surprise you and actually run? Worse case you are sitting at #1 again.
Sounds like a no brainer. Of course, if you really get desparate, I still have another Mopar BB sitting in the garage...they tend to keep on running (though I've done the same thing that you did)...