These guys might be in Vancouver:
http://www.pokerchipsets.ca/index.html
In general though, your best bet is usually over the Internet at a US company. And make sure you get US Postal for delivery and not UPS. UPS will charge duty and they will do it automatically on your behalf and they will also charge you to do so.
I have had poker supplies delivered by US Postal that have not had duty charged. It seems to be hit and miss.
As an example, these guys:
http://www.pokerchipsgalaxy.com/category/183698 are Canadian but they buy their chips from the US. Their prices are pretty reasonable but note that they are in US dollars. For shipping, they have a US Postal box for about $35 that holds up to 500 chips. The case though needs to go UPS.