If you have a sample of what you want the paint to look like, get some mixed locally where you live. Any automotive paint store can do this and might even mix you a small sample for free to use as a test.
Or, sitting at the same paint store, pick up one of their sample books. They will have something close that they should be willing to adapt to your precise color.
Then buy the reducer for that manufacturer's paint there at the store. Problem solved.
Rick
