any enamel spray paint will easily rub off an chip and peel and will be easily softened or melted with simple oil like wd40 or misquito replent on your hands.
I have had the best luck using duplicolor truck bed line in clear and applying it directly to the stripped bare riser and then using either semi gloss or flat black laquer paint over the textured clear.
This is the most durable finish and easily touched up , outside of powder coating or profession 2 step automotive style paint systems.
The people that tell you to use enamel spray cans don't know what they are talking about, the paint is junk and only good for back yard fences and wood . Anything that is handled or exposed to a lot of wear should never have the cheap enamel spray paint applied.
If you don't believe me just buy a can of laquer paint from a automotive store and then compare it to any enamel spray paint out there and apply it to some test metal surfaces and you will see how simple oils and household solvents will eat up enamel paint , where laquer paint is chemical resistant to most of them.
Most important quality laquer paint can be wet sanded and touched up , enamel will just blister , peel and chemically blister when tried to be touched up or repainted even in a small area.