Link fail pending.
I've used both Zumiez and Karmaloop. I will say that Karmaloop has some pretty good costumer service.
Also look on PLNDR.com. It's run by the Karmaloop guys and you can get some sick deals, not only on Supra, but on some other brands.
PM me if you have anymore questions on Supra. I've been a fanatic for about 4 years now.