I'm considering buying from makerbot: the NEMA 17 Hybrid stepper motor and the stepper driver to go with it. I purchased this stepper motor , 125 oz-in, but it seems too big and heavy is for our purposes. This has about 5x less torque than the one i bought, but I guess we will test it to see if it holds up...
fig: stepper motor and motor driver from makerBot
My only trepidation is I bet we can get SUPER cheap steppers from a supplier in china... so perhaps that's a better idea. And I believe the Sparkfun easy driver would be sufficient, or we can get the h-bridges and print our own boards eventually.
But first we have to find the correct torque for the motor...depending on the boat's flexible-inducing needs.