Waoww !
Bryan, you definetly have an HAWK EYE
You are absolutely right with Cdr MAY reference book :
It contains only a very precise description of the RNAV badges (P.105)
But the description was so accurate that I have taken the liberty to produce these two RNAV sketches by a transformation of one RNR 1891 and another victorian 1879 badge - thanks to photoshop !
This was done long time ago in order to complete my private documentation and in no way to abuse someone ...
Hope this will be considered as a venial sin
again BRAVO ZULU to Bryan.
a+