I came across an acrylic bezel which I believe is for a CWC RN Quartz diver issued around 1985-86.
All the markings and fonts seem to match perfectly with the bezels from the above period.
I would be really thankful if anyone having an issued quartz from the 80's could confirm the hight of the bezel.
Mine is 3,65mm and a good fit even on my RN Auto Date from 2004.
Many thanks,
Csaba