Here's an NOS 216 valve cover I've had in my shop for some time (first photo). Dark gray, but maybe not quite as dark as Dave's NOS parts.
Just an FYI, for anyone looking to duplicate the original blue of the US car engines, the DupliColor Chevrolet Blue DE1609 engine paint is a good match. It's medium dark, and sort-of a gray-ish blue. If I'm not mistaken, it's the color recommended by the VCCA.
And here's a valve cover I refinished for a '53 Bel Air 235 last year, as an example. Primed, then the DE1609 Chevy Blue. Decals added, and sealed with two coats of DupliColor DE1636 Clear. The decals changed for model years after '53, but not the basic engine color used in the cars (subject to factory variation in paint shade, of course).
