Going to Canada might not be a problem. It's the hassle-factor though if you use USPS. You have to fill out a form because it's going to a foreign country and the pay whatever it is. Your box doesn't sound like it'd be too heavy or big, and that is also a factor.
I've seen people send things via FedEx to other countries, and its less hassle but much more expensive. The only way to know is to pack it up, and take it to the post office, because with the USPS, you wouldn't get accurate information on the internet, either.