The first year of the new badges they were colour matched to the tanks.
So there was red, light & dark blue, green, yellow & black that know of to date.
When the original batch of matched colours ran out BSA reveted to the generic black or red.
The last set of light blue ones I know of changed hands for over $ 1000 Aus.
As the USA & OZ got their bikes before the UK it is no beyond belief that the UK only ever saw the black or red ones.
AFAIK Motoplas the BSA subsidary that made them got sucked up Dennis Poore in his government funded asset strip.
As the popularity of thermo setting plastic badges on cars, fridges, radios etc wained they got sold & resold & sold again till finally they became part of Wassal