David,
Take a look at this .... I cropped then enlarged the photo on the left of the second attachment you posted about the Shotley event.
.... and now a shufti at the Trophy being presented to the Cardiff in this link to the WNS Ceres Class
(copyright prevents me placing it here) - scroll down to:-
The Arbuthnot Trophy for Marathon.
Won by HMS Cardiff in 1922 and 1924.
and view the trophy ... a sculped male form mounted on a plinth - left arm raised - at a lean - left leg extended straight - right knee bent ... is that a replica being presented in your pic?? ... it is certainly the trophy at the centre foreground of the middle top photo in the group.