Swan 431 original prop shaft taper ratio?

i still have my original folding propeller and the existing propeller shaft has corossion, including excessive corossion on the mating surface of the taper. While I'm waiting for longer caliipers to arrive, does anyone know what the original taper should be?

For anyone that may see this post in the future, I took the prop and old shaft to a machineshop. I got a new propshaft. It appears that the prop was not fully seated on the last one. There was corossion on the last 1/2" of threads on the shaft, and on the taper signifying that it was exposed to seawater. I had to clean the prop screw with a wirebrush ion a drill. Once cleanred it was able to fully thread onto the new prop shaft.