GDHE-50-NG - AO Smith GDHE-50-NG - 50 Gallon - 100,000 BTU Vertex 100 Power Direct Vent Residential Gas Water Heater (Nat Gas)
Is where I got mine from, not sure if the free shipping is good to Canada.
That 6 year warranty worried me a little as well, but it's a warranty for commercial use, so the glass lining should be good for well past 6 years, although in theory a stainless tank should last decades if built right.