Hi,
you want to go from Vancouver to Washington? There is not much Canada on the way ...
Shop: mec.ca - don't know what they stock for bicycling but I guess e.g. their own label and things aren't that bad. Online-order is only possible with a canadian address I think, worth to visit a store in Vancouver. Go to Vancouver Island. There should be a ferry to Seattle from Victoria or so.
sorry, I don't understand you planned route, from Vancouver to Mexico City, Pacific to Atlantic ...