Canada, Ottawa?- Lennart Hagg born 1919

[Lena Gustafsson (Lenag)]

I am turning to this forum to ask for help in finding a man called Lennart Hagg (Haegg, Hägg). He was born in 1919 in Sweden (Villberga parish) and emigrated to Canada during the 1940:s or 1950:s. Last known residence (from 1984) is in Ottawa, Canada (I also have the street and number, but I don't want to publish that on the internet). He has been married to Stella (they separated, not on very good terms, about 1960) and has a daughter named Sylvia, who may be living in Great Britain. Lennart  worked for the Canadian government, probably with something connected to the army.
Lennart's nephews in Sweden need to contact him or his children regarding Lennarts brother, who died earlier this year. They have a swedish company taking care of legal matters here in Sweden who have not succeeded to find him. As they have been able to find other emigrated relatives by help of Anbytarforum (even if they were a little more ancient) they asked me to post this information here hoping that someone among the readers of this forum have some recommendations on how to proceed. We are grateful for any information or recommendation.
Best regards, Lena Gustafsson