I think most automotive spray paint usually holds up ok. That black
they sell to touch up merc outdrives lasts a while.

I was surprised to find out that anodizing at home was not all that
difficult. You can even color with ritz dye!

James Sweet wrote:
I had thought about powder coating the prop from my '69 Johnson V-115
but then I found it contains a rubber insert where it fits on the shaft
and I'm thinking the 400 degree curing bake would probably damage the
rubber. Is it possible to non-destructively remove that or is it bonded
in place?

Are any of the off the shelf aerosol paints durable enough to hold up
reasonably on a prop? I know some are readily dissolved by gas and oil.