I recently had this exact same problem. Further it was complicated by the fact that at the start of a big year of travel, I also switched residence from AB to NS, and NS said that despite having moved 5 months prior, because I hadn't spent 3 continuous months in province (due to trips), I wasn't eligible for gov't insurance. After that got squared away, I let them know I'd be gone for a while.
I ended up going with
http://www.imglobal.com/en/img-insurance/international-health-insurance/global-medical-insurance.aspxFor a 32/m with 5k deductible, was about $400 for the year, with exclusions for treatment in US/Singapore maybe Canada, and a few other expensive places. Was basically just the "holy shit" insurance for getting cancer or air ambulance, and moreso because it was a requirement for a tour I was doing. Is designed for expats, long term vacationers/snowbirds, basically anyone who's away from home a lot, and doesn't fit into the insurance industry's typical pigeon hole. Fair warning, I never had to make a claim, so I can't speak to what's arguably the most importance facet of a policy.
Make sure you inform the health people, otherwise your provincial coverage could lapse, and most third party insurance places I looked at said if that happens, then you'll only be covered for a grand total of 25k, which is basically like having no insurance at all.
As an aside the whole situation is incredibly frustrating. I researched it, and transient people, retirees wandering around the country in an RV, people who take a year off work to explore the country, despite paying taxes your whole life, and perhaps having never even left Canada, it is perfectly possible to end up with no health coverage.
In the UK/Australia where gap years are a lot more common, there are literally hundreds of companies offering reasonably priced travel insurance for periods of 1-2 years. Blows me away how they're so far behind here.
