[Van down by the river]

I think it's commendable that you want to try to do it yourself.
I question the motives. To save a few dollars? To get something you think can't be acquired from your local aquarium shops? Have you given them the opportunity? What is it exactly that is worth the trouble? I've seen almost every colored coral from the states in Canada as well. Many even in some of the many Canreefers tanks.

Everyone keeps telling you to call customs and it seems from the replies that you keep avoiding this step. Customs will not take kindly to a person trying to weasel through the rules or loopholes. If they feel that In anyway that your shipment is not declared properly they CAN and WILL seize it no questions asked. The seller will have no responsibility in this, he knows if there is no re-export cites it will not get through customs.

As to mislabelling and taking a chance, I think is a big disservice to the hobby. Being both reckless and showing no concern for the animals whatsoever. Would you try to sneak a family pet or child across if there was a chance of losing them? Certainly not. Hoping the customs agent will be careless and unobservant should not be an option.

Of course the shipper is willing to send the shipment. He's already been paid.
You are just a hobbyist with a small order and if he never hears from you again his business will be no worse off. There's a reason many US companies don't ship to Canada, it's not worth their time unless it's a store doing a larger order.

I think that doing your homework is in order.
I think that the end result of that would be that you will save no time or money over buying it locally.
If there is demand for an item, stores will attempt to provide it. If they are unable to aquire it, contact Wendell at Ocean Aquatics or John at JnL's