Right, right. I believe prior to the fuel economy-related rollbacks in the 70s, Canada had some higher limits (75 perhaps?) but not until BC's increase a couple years ago did Canada again see 70MPH+ limits. AFAIK, BC's highest limit in 1999 was 110.
Not a surviving relic, but certainly pre-metric. Although I have the archive classification, I can't find the exact date ― probably around the transition.

A-20 (Trans-Canada Highway), approaching La Pocatière. Bibliothèque et Archives nationales du Québec (E10, S44, SS1, D73-378, PD5)
The view now.