Finally!
I don't have a pesticide license valid for Ontario, so I can't buy Permethrin as used in many agricultural contexts, including on horses and other livestock.
However …
I had some Sawyer Permethrin clothing spray from REI brought into the country by a friend.
Also, I've found that I can import Permethrin (Ultrathon permethrin spray, 3M) via Amazon — and it made it through Customs no problem! The same price US$ as the REI stuff, though half the volume for the same .5% concentration, plus I got seriously dinged by import taxes.
Then, today, in downtown Toronto, opposite the well-known outdoor equipment coop, at the other place (that doesn't really seem to know their stuff but carries a different and equally good selection of brand-name stuff), I found the same Ultrathon as I paid through the nose for from Amazon. It was an acceptable price … steep, but worthwhile.
So now I have enough permethrin to treat my clothes and gear! Yippee!
Bruce Traillium