Rangoon red is a Ford color from the '60. Any competent Auto paint supplier should have the formula, be able to show you a sample and mix it for you on the spot.
Very few paint stores have ready made paint anymore. Paints are mixed according to formulas. It cuts down on waste, inventory and allows you the ability to get a either a better match or customize the color to more exactly match what you have in mind, instead of just taking what the paint store has in stock.
Although the paint supplier may not have the current formulation on record, it only takes a call from the paint store to the paint manufacturer in order to have the formula faxed back to them. I recently did a 66' tahoe torquise BC/CC and that is all my R&M dude had to do.