Any decent powder coat shop should be able to get you a pretty good color match. I have a Scion xB that I wanted to color match the wheels and some other parts and Prismatic Powders was able to get me an almost exact match...only downside was the $500 that the box of powder cost me but I now have my own box of powder sitting on a shelf down at the powder coater. I doubt I will ever use the entire box but I 'visit' it every time I go down there to drop-off or pick-up parts.
I'd stick with a 'stock' powder, which should get you close.