"Pure" ammonia? Pretty sure that's illegal. You could try ammonia extract, which I'm sure you could find at Home Depot or Canadian Tire. It's 10% ammonia and works just as well.
True "pure' ammonia is a gas but we say pure ammonia meaning it's nothing but water and ammonia. No perfumes, detergents, dyes or surfactants. In the US, most grocery and home improvement stores have it in the cleaning section.