RE: New to sailboats and could use a little help
At the present price of modern servos, and needing a new TX and R, I would just look for a dead including servos.
Sanwa gear (from memory) was good, but their idea of having a non-standard pin-out was a pain in the butt. If nobody else has the definitive cure, the best way would be to check out the RX pins with a meter. Use the resistance scale. If you know how the battery connection plugs in, you can figure power + and -. These will show as zero resistance when testing between pins. That just leaves the signal wire, i.e. the one that's left over.
Alternatively, with the lid off, there will be an electrolytic capacitor somewhere near the pins. It will have + and - markings on it, relating to its mounting pins. Trace the tracks back to the plug pins, and again, you have the important clue as to which pins are which, and therefore how to re-order the plug wiring to go in the present day standard of -, +, signal from the outside edge inward.