A bit of googling led me to a thread from 2006 on an Australian cycling forum. Which may be a total red herring/utter nonsense, but you never know.
https://www.bicycles.net.au/forums/viewtopic.php?f=23&t=19887
My inverted Coronation has a serial of 3P 1468 which is located on the seat collar on the seat tube.
I too have never seen mens version of the Coronation however but I do know of a friend who has a chainring which i have seen with crowns cut into them much like BSA had shaped into theirs. I cant remember the make/model it came off but I would think that this chainring shaped with crowns would've been off these models??
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Silverlight, I was told that several chainrings with the crown were made and given to various countries as a gift. Each country was given one only. A long time bike store owner in Sydney had one but I recently heard that it was sold to a private collector. This information was provided by a reputable source it is just the number of chainrings that were given I am unsure of.