Hi, Ed,

Maybe some of the AG experts will be along soon (matt4x4, where are you?) to give you a definitive answer.

IMHO, it should be fairly straightforward to sand down and paint with a good spray enamel.....like Rustoleum. The issue will be trying to match the existing paint.

Depending on how picky you are, you may want to repaint the entire coping rather than trying to match the existing.

Whatever you decide, you should have fairly good success if you use good painting techniques.

Ed, there may be something special for coping but I'm not aware of it. Let's see what others say.