Isn't the frame just gloss black? I would think you could go to an auto store (like Advance or Autozone) and color match to be sure. Usually they'll let you take a couple outside to match if you bring your bike.
I don't think you want to spend the money to get the OEM match from Colorrite unless it was the tanks or fenders.
I was looking at my frame the other day, trying to figure out if I want to add some reflective black tape to the frame (from the vendor on this forum). So, the frame would look the same in day time and light up at night. Maybe even more so with the LEDs on. Just an idea.