OK, I'll spill the beans...
it's actually 3/8" chrome wheel well molding
$10 for 20 feet, self adhesive with 3M tape.
Did every other slat in the stock lower and I'm happy and saved some buck$.
I originally did all the slats and it looked billet, but didn't match the upper so I peeled 2 off.
That's the cool part, if you don't like it, peel it off and you're out $10.
Door trim won't work very well, it comes in 2' lengths (too short) and it's too narrow anyway. That was my first idea.
I guess you could buy it by the roll, but the horizontal slats aren't deep enough without notching it for the uprights- that would be a big PITA
:k