need help with bear bows

[stevewills]

got three bear bows i would like too date
first is a bear blackbear 60''45# has canadian patent KL7866 i think its a copper medalion.
Second kodiac magnum 52''45#ku98903 silver medalion no canadian patent.
Third is grizzly kr38392 58''55# silver medalion no canadian patent......please help me wondering if with the last two i got a birth year bow thanks steve

[vermonster13]

1970

They dropped the Canada 1953 mark after 1972.

The other two are later 70's bows.