What you are trying to do is the most difficult thing in painting to do, in my book.
Easy to do on small panel, like a cycle tank but to do a whole car and get it even and the % of sheen you want is no easy task.
Like one jobber told me a year ago, I love this type of work because they will be back buying the same materials again to redo.
So all I'm saying is get the right paint code and the brand you want and get a premixed matte clear, too make your life easier and also to avoid the nightmare of messing up one fender and on the redo, it don't match.
A six inch test panel with the right products, is all you need and that won't waste anything.
there seems to be nothing custom about the picture you posted, so no doubt, it is just a factory color and a standard matte clear.