Ended up grabbing Rust-Oleum High Heat flat black(rated for 2000'), but it recommends using their high heat primer as well, but not sure if that's such a good idea with the valve cover(I assume I've been using the wrong term). I grabbed them both because I do intend to use the primer + paint for the heat shield.
Chaos did you prime it when you used this?
All the engine enamels I saw were only rated for 500'