I think the only recommendation I would make here is to make sure they use PPG DBC #1 base coat, and a high solids clear coat. My favorite is PPG 2021 or the like.
Because the paint is PPG from the factory it should be easy to color match it, remember your basically butt matching this paint when you are taking them off and repainting it. There won't be any blending. So, the, "oh it's really close" might not be so when you put it back on the car. Additionally, a high solids clear will prevent shrinkage, and also will harden like flint when your done. It's important because it's close to the road way, and you want it reticent to rock damage thrown at it. If you use a production clear coat (what body shops usually use) you can have shrinkage or it can start to peel. I have this on my GS now where someone decided a quick refinish was the way to go. It's a half dollar size clear coat hole.
All that being stated you could do two things. Order the base coat/clear coat for the painter to use, or expect to pay slightly more for a job well done if they order it. You shouldn't need more than a quart of each product.
You could use a different high solids clear, but I don't think I would go with someone else as far as the base coat.