Unfortunately living in Canada we are basically SOL for online vendors compared to how spoiled the states are. The only vendor really is J&L and even then you'll spend a ton on shipping them, to the point it may end up being close to same cost.
Living in Kitchener I would say I'm somewhat fortunate for stores in my area but the majority do offer discounts on bulk numbers. Average cost for me here is $2-3 a hermit and $2-$4 for snails depending on species. $2 for Astrea or Trochus and $4 for large Mexican Turbos. Have you tried asking about bulk deals? Don't forget your comparing to US pricing where everything is cheaper no matter what it is, basically comparing apples to oranges. I assume there isn't even any crappy chains like Big Als in your area either?