your not allowed to import them according to US law. However, your not in the USA and your a canadian, so these laws don't apply to you. I'm not familiar with canadian law so there may be something that says you have to observe the importation laws of other countries......i've no idea.
worst case scenario: US customs finds the laser and destroys it.
then you have to decide who is responsible. Most of the time the seller is responsible until the product arrives to the customer in the condition it was purchased.
this case is different since goods are being illegally imported.....
I would just make sure the customer knows exactly how your products are packaged and labeled, and make sure they understand the risk of spending all that money, and the risk of it being taken away....