Choosing the colours of House Arryn, Game of Thrones

A simple online search reveals a confusing range of colours being used to represent House Arryn, one of the lesser noble houses in George RR Martin's Song of Ice and Fire series, more popularly known by the title of his first book Game of Thrones (GoT) in the HBO series. From dark blue to greyish blue to sky blue, I was spoilt for choice and that resulted in my miniature paint conversion project