It might be worth talking to Peninsular and Orient, as they have/had a decent archive, and the archivist was Stephen Rabson.
Also possibly try Veronica Sekules at UEA. If Duncan Wallet supplied the Canberra, then they would have been answering to Sir Donald Forsyth Anderson, at P&O, and his design chief for interiors, Sir Hugh Casson. DFA was the younger brother of Sir Colin Anderson, of Anderson Green, who revolutionised ship-board design from the 1930s onwards, with the assistance of the very talented New Zealander Brian O'Rorke.
If DFA followed his brother, then the glass would have been made by medium to top quality UK manufacturers, and info should be available in P&O's archives.