I need to paint the grill on my 1990 W150. Any ideas on where to get???

A 1990 has a plastic grille, right? What color are you looking at? Most guys I know paint them with a spray bomb, and they have those in cans specific for plastic in several colors.
Our local Farm & Fleet has the Rust-oleum spray bombs for plastic as does our local Menards for around $7 a can.I would think one can should do a great job covering it.

2 types of paint for 86-90 grilles:
if a standard grille, then regular argent should match closely. its flat/eggshell type
if a LE grille with the chrome, then its a oddball dark argent. this is more of a semi gloss on the flat side of that

both paints have multiple options as they were used on the muscle cars too. as well as some darn close matches otc

As a side note you could look for SEM Trim Paint as well. It's more than the store stuff but, better or at least it used to be in my experience.

The grill is plastic, yes. I was mostly looking for the name of the color.
Thanks for all the replys. Off to the hardware store.