Been thinking about gaming that one myself too.
Commando Miniatures and Eureka Miniatures both produce British Army in shirtsleeve order for Aden, Borneo, etc., so they might work with a suitable head swap.
Regiment Games did produce a WWII Naval Landing Party that included an officer or two that might work, but I think they have now closed and I don't know if anyone picked up those particular figures. Pulp Figures do a pack of Royal Navy Deck Crew, but the officer is in tropical rig, though there is an officer or CPO type in the equivalent American pack in a collar and tie.
The more important question though is where to find a suitable figure for 3rd Officer Blythe?
Pete