The large signet ring that Commandant Razinski wears on his right hand little finger was one of Marius Goring's own. He wears it again many times in The Adventures of the Scarlet Pimpernel (1955) as Sir Percy Blakeney and in The Old Men at The Zoo (1983) as Emile Englander.
The aircraft that Gray boards when flying off on her mission is a Douglas DC-3 Dakota, G-AGHL, operated by USAAF and RAF until 1946, by British Overseas Airways Corporation and British European Airways until 1960, and then by Ghana Airways until it was 'destroyed' in 1969.