“Pussers” is a slang term that refers to the Navy. Therefore, the Walrus would be the Navy’s Spitfire (very tongue in cheek!).
My father’s cousin served as the ship’s surgeon on HMS Anson in 1945, after serving on various ships (and being sunk at least once!) in the Mediterranean, and witnessed the Japanese surrender in Hong Kong. He to has passed away, unfortunately.
“Pusser” is an old English Navy slang term for “Purser”
http://en.wikipedia.org/wiki/Purser