Chrome parts

Molotow chrome pen. Hands-down.

You can find them at hobby lobby or any hobby store worth a dang.

Looks like real chrome.

Ya I'm kinda taking a break from armor right now I'm building some old custom street rods (boothill express, beer wagon ect.)

I will second GMorrison's advide. Testor's MM chrome is very bright and good for brush touch ups if you're not going to strip and airbrush the part with with something like AK metals paints polished/bright chrome.

This is seen much more in large parts (gas tanks etc.) in auto/truck modeling than in armor.

Testors Model Master Chrome Silver. It's not invisible but it is a reasonable general fix.

Sometimes you can re-wrap a round part with chrome foil like bare metal foil.

Some guys touch up the bare plastic with a silver Sharpie. Other guys dechrome the whole part and repaint OR send the parts off to companies to have them rechromed. There was an article in scale auto Mag recently that talked about using malotov markers (spelled that wrong most likely)