British Plastic Rank Stars and Crowns

During WWII the British manufactured a large number of cap badges in plastic, they also manufactured Officer's rank stars and crowns.   I have a Tank Suit with plastic Captain's stars on the epaulets, has anyone ever run across these being used on Canadian BD?

I have never seen it.
But i doubt that it has never been used by the Canadians.
I also would like to see some examples.

Years ago I spent an afternoon with an officer who served in the Second World War. In his box of badges etc he had some plastic rank stars. I didn't ask him if he had worn these. Of interest, he also had printed captain's rank on a strip of canvas. I have not seen those in wear.