Is there a paint code for the AC vents?

It's the metallic element that makes that hard to match.
I'm not the authority on it, but as far as I know there is no paint code for an exact match.

 

@Elektroingenieur might know.

A body shop could match it, but that more'n likely exceed the cost of just replacing the parts. Which is another option to consider.

Maybe try disassembling it too: if you can manage it all the options become easier I think.

If keeping it "stock" is not paramount, consider something like satin-black Plasti-Dip? it's available in cans (for dipping), or a spray can. Mask-off carefully and spray with the latter?

Is this @3prongpaul's video? I might show the vent removal, I forget:

 

Compared to many other cars, they are fairly easy to remove (search radio removal/installation videos). With a screwdriver and plastic trim removal tool, I would remove all, disassemble and paint/clearcoat.

GOOD LUCK!

 

I wouldn't recommend plasti-dip for items that are operated/touched or are regularly cleaned or protected with chemicals. Plasti-dip is great to test out color choice or design ideas.

 

I've been down this road in other cars. Usually the best way is to find a color you like and then paint all the interior trimbits you care about so that they match each other. That's a much easier task than trying to match the factory finish.

Hobby shops have paints with metallic finishes that adhere well to these plastics, though hobby finishes often aren't very durable. You'll probably need to add a clear coat with something else to add scratch resistance.

 

Yeah, even if you match existing paint, a newly painted single panel will stand-out. Good idea.

 

@The Electric Me is correct. There are codes for the interior trim colors, but as far as I know, the specifications for the colors and finishes are proprietary to Toyota. It’s not like the situation with exterior colors, for which Toyota and others sell touch-up paint and paint systems to match.

On the U.S. version of the certification label, inside the left front door, the four-character interior trim code appears next to C/TR, after the slash, but I think it’s meant only to help find the right replacement parts in the catalog. Typically, the first two characters identify the type of fabric or leather, and the second two characters identify the trim color. (The three-character code before the slash is for the exterior color.)

Toyota part numbers can have color codes, too, usually in the eleventh and twelfth characters. For example, some of the interior trim pieces used on 2008 Prius cars have part numbers ending in “-A1,” ”-B1,” or “-E0,” for ivory, gray, or grege, used on cars with trim codes __0_, __1_, and __4_, respectively; a “-C0” suffix often indicates a part that is black or nearly so. The color names in the parts catalog aren’t necessarily the same as those in sales brochures, by the way.

 

There is a Rustoleum spray paint "Hammer finish gray" which is a very close match, in a shade of metallic gray, to the existing finish. If you overapply it, the hammered texture will become apparent. Start with a clean and lightly sanded surface... go easy with the spray; when dry, buff it with fine emery cloth, and clear coat it, and it may turn out close enough.