Royal Marine Type Cap with Kings Crown Black Buttons (Postman's?).

[leigh kitchen]

Does anybody know what this is please? I've had it for over 30 years, it is the same as a Royal Marine cap other than it has black painted Kings Crown buttons rather than yellow metal "dog in a basket" ones.
I've always thought of it as perhaps a GPO Postman's cap, or perhaps museum / palace staff.

[GTB]

Possibly worn by former Government Messengers?

GTB

[leigh kitchen]

Thanks, that's a possibility.

[leigh kitchen]

Just a bump.