I have ordered from B&H Photo in New York many times. They have very good prices and a very good selection of used equipment at very fair prices. And most importantly, they ship fast and cheaply. I usually pay between 8 and 12 dollars for shipping. Plus, they pre-calculate Canadian taxes and the small duties or brokerages that apply. Thus, they are the least painful US company to deal with, bar none.
And to top it off, their customer service is astonishingly good.
I bought a used 100-300 Panasonic stabilized lens for $379, which is very cheap for that lens. It came in excellent condition and has worked pretty much flawlessly since I got it. When I ordered, I figured I would throw in a battery for the GH2 and G5, which share the same battery size. It cost me $14.79 and shipping was included in the one low price.
I received the lens quickly, but the battery took an extra week. And even though it was shipped separately via Purolator, there was no extra charge. Wow.
But it arrived DOA. It was in the ubiquitous plastic case that had to be cut open, so I know it was brand new. But neither charger will light up, and neither camera will function with it. So it is a brick. And certainly not worth shipping back at such a cheap price. Still, I mentioned it on their customer service site, and lo, and behold, they shipped me a new one.
Can you believe that? Awesome service … believe me that, if you have not tried these guys for camera stuff, you really ought to. Of course, be aware that they sell American goods, so Nikon equipment specifically is not warranted in Canada. You will need to ship south if you have problems. On the other hand, I don’t mind the risk for used equipment since there is no real warranty on that anyway.