I'd like a car as close to the old BRG as possible. I'm thinking 1930 Bentley.
There was never an 'official' BRG, and 30's Bentleys were nowhere near as dark as modern interpretations. Only the metal parts of the body - bonnet, scuttle, wings - were painted green. They weren't metallic either
Not true.
There was a British Racing Green. A Triumph shade in 1974 was called British Racing Green and was available on the Dolomite, Spitfire, Stag, TR6, Toledo and the 2000 / 2500 range.
I have a Triumph colour chart dated 1st Seotember 1974 with it listed as a colour option.
Britush Racing Green was also available as an option for Triumph in the American Market in 1967. Manufacturered by the then paint manufacturer ICI, it had the paint code BRG 2855.
Some manufacturers had Racing Green for some models, but there definately was a British Racing Green as stated above....