I'm currently doing my Master's and I want to do a co-op course in Canada in HR or marketing. How feasible is it?

Hey, YES! A co-operative education not only provides you with the practical experience of the work environment, but it also pays as well. The company you will work in will pay you during your tenure, which in turn helps in managing finances along with building an impressive resume.

 The best universities in Canada that offer co-op programs in their courses are:

University of Waterloo
Wilfrid Laurier University
Simon Fraser University
University of British Columbia
University of Victoria
Centennial College
University of Quebec
University of Ottawa
University of Calgary

Co-op programs can be a propelling factor in your career’s growth as they put you ahead of your peers in the same duration of time. It provides you with relevant experience, an excellent resume, professional behavior, payment for your tenure, and a great network in your field for your future endeavors. 

Hope this helps. Do let me know if you have any more questions.