RE: seawind?
I would think that might be a little on the low side (torque). THe smallest I've ever seen used with a SW is a Futaba 3802, (to make this servo fit the stock servo tray modifications must be made because it's made to fit a servo with a larger case) which with 6.0V power (recommended) you get 153 ounces--20 oz. more than what you're talking about. The person using the 3802 was one of our club members, and to my knowledge it worked ok. The 3801 has 194 oz. or torque and like I said is the servo preferred. Make sure if you DO choose the 3802, to make sure that whatever modifications you make are class legal (SeaWind Class Owners Association) if you want to enter any SW class regattas (which you may not). The 3801 servo requires no modifications--the servo tray is designed specifically for it. It usually runs about $55 + shipping or tax (if you're getting it locally).
The nice thing about sailboats is, yes the cost of servos might be higher because the torque required is higher, all you need other than that are batteries (a good 6.0V NiMH pack works great--I have a 3300mAh pack that allows me to sail for 3-4 hours). No fuel will ever be needed (just the wind)!
Andy