From what I can see the P.8 was used by the RAF, RAAF, RCAF (and other commonwealth Air Forces). It was manufactured in the UK and Australia (in two locations) and probably Canada.
Hi Mike
You have opened an interesting can of worms
Are there any other markings on the unit you have? If it says 6A/726 or 1277 I am
guessing that it will probably be UK made. G6A units were Australian made for RAAF and interchangeable with the 6A/726. As you can see there were at least three different versions of the P.8 though how the RAF decided to sub-identify the luminous and non-luminous is not known to me. J.129 is a CAC specification.
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