Referring to @MaxMaker post, I create a new thread in order not do jam the “No drilled masts” onee
Since we’re in water, and the vessel light (70 to 120 kg all included) I think that compressed air would do the job nicely. 30x20x10cm sized suitcase oil free 180L per minute 1100W cost 40€ from Action, 60€ from LIDL. Then, I think the rotative core from pneumatic wrenches like the LIDL one requires bigger compressors because they have to deliver a 11 to 15 mN torque for each bolt of a car wheel … would be interesting to have an insight into smaller air engines … One big issue with those small oil-free air compressors is their pour duty cycle eg 10 minutes on for 10 minutes off.
Maybe the small 3-4 bar compressors for car tyres could do the job if the duty cycle was OK.