British Officers Cap, WW1 or WW2?

[dragnet]

RA officers cap, im not sure what date, might well be WW1 or early 30's, has a good shape and i do like the silk type cushion to the top, also like the number of airvents, its just a shame that the makers details cannot be made out, the only clue could be the name and number to the inside, Sumter/Sunter number 5320, is that an early number?? Any help would be gratefull. Pete.

[dragnet]

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[Bond]

A later example Pete, going by the cloth covered underside to the peak and the thick chinstrap, 40's or 50's, it could be WWII or just after, though pre 53 from the badge (&buttons).

Jerry