This is for plastic, I thought of the spray but the masking would be painful.

Both sources I suggested included plastic. If your going to try the chrome in a can method, try the spray bomb method on something expendable before going ahead to make sure the finish is what your looking for and to try out your masking capabilities. Good Luck

Try Michaels craft store for a chrome paint marker.Works for me.

The model car guys use a product called Bare Metal Foil to do chrome trim.  It's bascially  really thin foil with an adhesive backing that comes on a sheet about half the size of a sheet of letter-size paper.

To apply it, you trim it on the sheet using a sharp X-acto knife, peel it off the sheet and apply it to the part.  Then smooth it down being careful to avoid wrinkles.  You can then trim off the excess using the hobby knife and polish it with a soft cloth.  If you make a mistake you can peel it off and start over with a new piece. 

It takes some practice to get it right, but it does look convincing on a model car.  I've never tried it on a car interior but it might be worth a shot (?).

Here's a link to their website:
http://www.bare-metal.com/bare-metal-foil.html

There's a slide show there that explains in more detail how to use it.

You can buy it from their website, but most hobby shops also carry it, if there's one near you.