Tom,
To work in Marketing in this country you need to understand the population and the trends in the market. The Canadian market is different than the American market, and within Canada there are variances in relation to different cultures and geographies. To be successful in that field in Canada, one must know the market. Also, there are greater chances of someone coming from abroad getting employment with a technical background than there is someone with a marketing background. Your MBA could be a great asset for you but my advice would be to study Information Technology, preferably in the E-Commerce area. Your business savvy and technical knowledge would potentially make you a great catch.
Best of Luck,
Harry