Noah's pet ark usually carry anacharis. Their location is in the heart of kitsilano(Broadway). Call them or drop by if your closer. Good luck with the search. Ask some of the sponsors here as well or have a look in the classifieds.
Aquariums West definitely had some Friday but you would be paying double the price as anywhere else. Check out Main Aquarium(he had some last time I was there) and North American Pet Store on Kingsway and Nanaimo too. They will all be much cheaper