Toronto-Dominion Centre

 The Toronto-Dominion_Centre started with two towers. While the tallest was the tallest office tower in Canada, the 2nd tower was comparable to the tallest in Montreal, at the time if its completion.

https://upload.wikimedia.org/wikipedia/commons/thumb/b/bd/CN_Tempo_service_to_Sarnia.jpg/640px-CN_Tempo_service_to_Sarnia.jpg

The Vancouver TD stump is only 10 feet taller than the Fairmont_Royal_York, which is 124-metres-tall (407 ft).

Then a Vancouver size stump was added, its only 417 feet or 127m.  When TD_Tower_(Vancouver) opened in 1972, it was the tallest office building in BC, at only 30 stories. 

 https://upload.wikimedia.org/TD_Tower_Vancouver 127 m (417 ft) its a few feet shorter than the CP Tower in Toronto.

https://upload.wikimedia.org/Canadian_Pacific_Tower (420 feet or 128m) It opened in 1974.

https://upload.wikimedia.org/wikipedia/commons/thumb/d/da/Toronto_from_cn_tower.jpg/640px-Toronto_from_cn_tower.jpg Observe the Vancouver size TD stump in Toronto.

The TD_Canada_Trust_Tower_(Calgary) would be the 3rd tallest in the Toronto TD Centre.

https://upload.wikimedia.org/wikipedia/commons/thumb/1/17/TD_Waterhouse_Tower.JPG/360px-TD_Waterhouse_Tower.JPG This 1985 building was comparable to the tallest office tower in Calgary in 1976. https://en.wikipedia.org/wiki/Stephen_Avenue_Place Of course because Calgary isn't under Vancouver building restriction, Calgary has some office towers that are tall even by Toronto standards. 

https://en.wikipedia.org/wiki/Toronto-Dominion_Centre#Towers