Consider what your end result and budget is first.
Chrome plating isn’t possible per-se, you should be able to do a polished vapor deposition process on RP parts but it is not an easy or in house process. This is the usual process for chrome plating effects on buttons and knobs you see on plastic parts.
The other problem is RP parts without substantial hand finishing or an excellent quality machine will likely look poor without preparation beforehand because of the base part quality. Depending on your budget/need painting with metallic silver paint on a highly polished part may give you the closest thing to in house. Or just machining from metal and polishing.
I am unfamiliar with any PVD vendors who would do low run parts but it doesn’t hurt to look and ask.