Welcome Sheila to the SBO Forum.
@Joe provides some solid sailing experience. The paddle wheel, speed through the water, and equipment require a lot of maintenance to keep functioning. The information it provides can be low in value in the scheme of things.
With the advent of GPS and tidal-current data from a browser app like DeepZoom.com, you can receive all the data used to determine your speed through the water and the navigational awareness of your progress to a destination with no paddlewheel maintenance.
The bonus is connecting the GPS to your plotter and using it with other data systems.
Rather than trying to make the original electronic hardware function, it may be less expensive to identify the functions you need and desire, then look for current hardware that gives you the resources you want.