BDL covered both of the primary Canadian web retailers (PaulsFinest and KnifeWorks) I was able to locate in an internet search. Suehiro stones seem to be almost unidentifiable from a Canadian (let alone Lower Mainland) retail site location.
The only Lower Mainland retailer which I can identify with any certainty as having any selection of stones is Lee Valley Tools, which (besides its Internet presence) has brick and mortar stores in both Vancouver (1180 SE Marine Drive) and Coquitlam (1401 United Blvd.). Lee Valley has Bester/Imanishi water stones, Norton water stones, King water stones and Sigma Power Select II water stones, each line in varying grits.
It's been a couple of years since I went into one of the brick and mortar Lee Valley stores, but be advised that this may not necessarily be a retail operation where you can get hands-on feel of the product before purchase (though if they have it in stock at the store you visit, you will be able to buy it then & there). In the past, you went in, browsed through catalogs, filled out a form, and the clerks went into the back warehouse and brought out your order to be paid for. Don't expect any knowledge of the product(s) from the sales personnel. Caveat emptor applies here, and you need to do your own due diligence research about the products beforehand. Still, the prices are the same as the catalog and 'net prices, without shipping costs (though including sales taxes), and the "shipping delays" are zero, compared to Canada Post or any of the private common carriers.
Two other brick and mortar sites are possibilities, though I was not able to confirm through the web that they had any water stones for sale, let alone Suehiros. Santoku Equipment Office, 107-1118 Homer Street in Vancouver (located inside the Empress Galleria) has a web site which does not detail any sharpening supplies for sale, and The Sharpening House, 5331 West Blvd. in the Kerrisdale district in Vancouver does not have any web site I could locate.
Coming south across the border into Washington State, there are two physical stores I have some knowledge of having water stones.
The Epicurean Edge (107 Central Way in Kirkland) has a number of stones, though many of the water stones are listed as being from "Misc Maker" as the manufacturer.
The other store, Hardwick's (4214 Roosevelt Way NE, Seattle) does carry some Suehiro's, but they are smaller stones (180 mm x 64 mm x 20 mm) than the size of most water stones that many sharpeners use. Also, while they are Suehiro's, I cannot identify where they are Rica Line Suehiro. Sharpening stones are kept at Hardwick's in a locked cabinet along the north wall of the shop, near the front window and closer to the floor than the ceiling (if you go to Hardwick's, it really helps to know where particular items are). Hardwick's does have a web site, but the web site is a pale (actually closer to gossamer) reflection of all that is within the warrens of the store. Be advised, however, Hardwick's is one of the funkiest places I know of (in a good sense) and you will probably spend hours in there diverted from what you originally sought.
I am also assuming that you are somewhat adverse to the hassles of transborder shipping and Canada Customs regulations and fees. An alternative is to have an order from the US shipped to a firm in Blaine which will (for a fee) act as a U.S. address to accept a package from a US retailer and hold it for you until you come across the border to pick it up. Combine that with package shipment tracking, and you will be able to know when the package has reached Blaine and is ready for you to pick up. You then cross the border at BC 99 - Interstate 5, go to the Blaine shipping address, pick up your package, and then return to Canada with your package. Look up "Blaine shipping service for Canadians" on Google for the websites of companies in Blaine which will accept your package for you and hold it for a fee.
Hope this might be of help.