Randy, one thing to keep in mind is that paint colors change with time, typically fading and becoming lighter due to oxidation and light bleaching. The color Tom Sr. saw when the paint was freshly applied back in the day, is not likely the exact same shade that you see today. As close as you can get, but just a shade darker, is likely the best bet for matching this old paint if you are doing a total repaint. But if you are just doing a spot touch-up, then you are quite correct in that you may need to get something special mixed to match.
Best of luck with finding what you need, and if you do find something you think is truly suitable, perhaps you'd be kind enough to share it here.