You're speaking of the valve cover.
If your VC gasket is old, get a new one and use hondabond on it.
If your VC gasket is new-ish, use it again and use hondabond on it.
Hondabond can be had at any dealership. (silicone rubber is good stuff but I prefer hondabond for gaskets on the motor)
If you paint you're valve cover red make sure to use wrinke paint (like factory) and take you're time with the prep, taping, and painting so it comes out looking as good as possible.
You could paint the VC some custom color however, its gaining in popularity over the tried and true wrinke red colored valve covers.