Hi!! I've been asking around as well for a HR Management PG program and the best recommendation I got are for George Brown and Humber. Someone from York University told me they were the best options...
George Brown is 3 semsters long, 2 in class and the last one is work experience.
Humber has 160 hours workplacement during its ast semester. 2 semsters long.
Sheridan and Seneca also has Co-op option, but I don't have references.