The Sun says detectives travelled to Canada to interview the man and he reportedly picked out a photo of 26-year-old Margaret Cook — his alleged victim.
The Sun reports that Britain's Crown Prosecution Service formally has applied for the man's extradition, but says Canadian officials are still considering the request.
Cook was shot in the chest outside a nightclub and the newspaper reports the man told investigators he shot her with a Russian-made pistol after she cheated him out of money and was rude to him when he complained.
The Sun says the man moved to Canada in 1951 and settled in Ontario, where he became a Canadian citizen and raised a family.
The report says the man — whose name hasn't been released — decided to confess to killing Cook after he was diagnosed with skin cancer two years ago.