I think those porous graphite looking parts like the foot pedal are dipped into a dye, or stained somehow and start looking gray when they dry out, yet look black again when they are wet. So I dunno. Maybe a light coat of spray paint (just a dusting, no buildup).
The aluminum alloy parts can be prepped (cleaned) with alcohol or brake parts cleaner, hit with aluminum oxide primer, and then painted (not too thick on the paint). A coat of car wax when the paint is still just a little tacky will give it a nice hard finish. That's how I refinish outboard lower units, mounts and exhaust housings and they stay looking good for a long time.