Use the Portaboat until you get to Panama. Once in Panama City you can stop by Marine Warehouse and upgrade if you feel the Portaboat isn't working for you. There are also Yamaha & Tohatsu dealers that have stock in on hand. We needed a new rib and bought an AB and Tohatsu 9.8 for a good price. I'm sure you could put a package together further north also.

My own feeling is that a lightweight (less than 110lbs) rib and an 8 to 10 hp is best for cruising. A 'get up and go' tender is always an asset. If you purchase the engine out of the US you have the option of a 2 stroke. Our 9.8 Tohatsu is 47 lbs. Ya can't get a 4 stroke that light.