*de-lurks*
Brantford representiiiiiiiin' *tries to make cool hand signals that are probably wrong*
Regarding the Canadian flag:
The current Canadian flag was adopted in 1965. Before that, the
Canadian Red Ensign was used even though it was never official. The maple leaf was already a common Canadian symbol long before the '50s time frame being discussed - The
Toronto Maple Leafs were the name of a baseball team well before the hockey team took the name in 1927, and
here is a picture of Olympian Percy Williams from, I presume, 1928.
So you can still use a maple leaf even in a pre-1965 logo, but to make it suitably "retro" looking you have to make the edges more curvy and organic-looking, as in the examples seen above, as well as
this logo the Maple Leafs of the NHL used from 1939-'67.