Anthracite wheel centre caps?

[Greeny.]

Hi, my wheels are power coated anthracite but my centre caps are stone chipped to s**t! I need to respray them but without going to bodyshop I dunno what colour would be a good match. I know all colours of anthracite will be slightly different but does anyone have any idea if any off the shelf car colour would be a close match?

Cheers
Dan