Congratulations on snagging such a great price! In Canada, the more costly the shipment, the more likely Customs officials are to examine the package and assess a duty and/or tax on its value, or even seize it. The smaller the shipment, the less likely it is to attract examination or assessments. Hopefully, all the ideological objections to IVM are history and they won’t interfere with your package.
To US Customs the issue isn't ideological, it is because IVM is prescription. They find it they will seize it.