I have looked into it. Pricing for those is a lot especially with exchange, duty, shipping to Canada. And Grand National or any other G that ram the 8.5 from factory are not easy to come by up here either! I wish I could go with one of the made to fit rear ends!
I don't know what kind of power you have but the 8.2" I have cost me $600, it's a Eaton posi and had the 3.08 gears I like and it still has the original clutch packs. The 8.2" is good up to around 500 hp, I'm getting close to that so I might have to remove some stickers.