I found my shade of British Racing Green in an odd place. When I built my Tamiya Lotus 25 Coventry Climax F1 car from the 1965 season (my first non-winged model in about twenty years), I had a difficult time researching the colors, because most of the photos I could find were in B&W, though I did find some color.
And then when I settled on what I felt was the closest color match, I couldn't find it. I tried all kinds of out-of-the-bottle colors and mixtures, and was happy with none of them. Getting desperate, I noticed a promising color on a spray can cap. To my amazement, it was from the Krylon Short Cuts series of small cans and the match was, to the best of my ability to confirm it, virtually perfect. It was the first time I'd painted a model from a can since I was a kid and you know what? The sky did not fall, lions did not whelp in the streets, it did not rain frogs and I did not break out in boils. And my airbrush forgave me. So, find these colors at an art supply store or the hardware store. I have since used one of the reds and a white from this series with equally good results. These cans spray with a nice, soft pressure and relatively narrow spray, ideal for model work. Good luck.
TOM