The valve cover is aluminum, it won't rust. What you're seeing is just some paint bubbling. You can repaint a valve cover vary easily, and you can also opt to have it powder coated, so it's virtually rust, ding, scratch, and oil proof.

As for the exhaust heat shield, that's just a thin sheet of stamped steel painted black. I don't even have mine on my car. If you really want to save it, you can do one of two things. Take it off, sand it and paint it, or just find another one in a junk yard, and paint that one instead. It's up to you, but I'd just remove it. Do you really need that little reminder not to grab onto a hot exhaust manifold?