Wow, thank you all! These are indeed great resources. The best car-guitar comparison I‘ve seen so far. Really tells the story of these custom colors.
I came across this article which mentions Blond as a kind-of custom color coming from the Telecaster.
http://www.vintageguitar.com/24640/f...-in-the-1960s/
So that fits right with what you said, Sergio, that it was an in-house custom color at least on a Strat.
Really interesting stuff with these colors. As much as we‘d probably like to have a definitive chart representing everything that actually was done back in the day, it‘s more fun the way is.