I have a 90hp suzi driving my SR5,4 and know lots of people who sail them it's very fuel efficient super and quiet (has a lock on it to prevent re starting!!!)
14'x21' prop should do the trick really well.
Engine weighs 158kg
Yam 2 stroke 90 is super to but nog new available and i would make the same decision again.
see on Avon Searider - Home
for few pics (look at member Rob Ubels)
115 is possible to faster but you hear it guzzling the fuel. (almost above the engine noise)
130 should go to but to crazy and to fast wouldnt do both
just take a 90 4s suzi or 90 2s yamaha