Just to follow on - I fully agree that it would be (the future) Edward VIII. It looks reasonably close to him, and the military cap would be about right for the post-Victorian era. So, it would date between 1911 and 1936. I would say almost certainly 1911 as it was probably made to celebrate the initial investiture as there's no other information on it (E.g. a 10 year celebration of investiture, or opening of -x- building/event by HRH PoW.).
Charles - Just doesn't look like him
George V - Had a beard in 1901 when he was PoW
Edward VII - Was only a month old when he was PoW
The last one before that was George IV in 1762 and that token is clearly not that old (plus military cap is all wrong)
