All resellers sell the P6000/7000/8000/9000 inks at the same (lowest) price under an Epson contract. The Canadian seller is actually more than US sellers at about $125/ea vs $89/ea.
But, Epson doesn't offer them as a bundle and only single. Some sellers may show them as a bundle option, but should be pricing them at the lowest cost per Epson's agreement. eBay sellers (if not authorized resellers) can offer them at a lower price.
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