When Albert tells Harold not to do anything stupid, because he does not want his ear coming back to him, it was a reference to then-recent kidnapping of Jean Paul Getty's grandson being held for ransom. When Getty refused to pay the ransom, the kidnappers cut off his grandson's ear and sent it back.
Galaxy Cinema, where Albert and his friends watch Enter the Dragon (1973), was genuinely found in the Steptoe's home turf of Shepherd's Bush. An early feature of its shopping centre, it had opened showing Please Sir! (1971) on 26th November 1971, and closed on 19th June 1975 with a screening of The Exorcist (1973).
Writers Ray Galton and Alan Simpson were inordinately fond of the name Dolly Clackett, who was also said to be a resident of East Cheam in their earlier scripts for Hancock's Half Hour (1956).