Even before the world ended, if I chose the economical shipping method, I found it wasn't uncommon for packages to take 4-6 weeks to arrive. Sometimes they arrived sooner. Sometimes later.
For me, there's always a black out period around when the package gets handed over to the Canadian carrier. There's no news until it arrives in country. During that time, my guess is it's on a container ship crossing the ocean or stuck in the middle of a canal.
Usually, after 6 weeks, I send an e-mail to the seller. They'll check up to make sure the package hasn't been stalled at a post-office. One time, that happened and the seller had to take the package back from the post office and resend it. Total time for the package to arrive was 6 months. It was a well known seller I've dealt with dozens of times, so I wasn't worried.
I believe you have 90 days to open a case, so give the seller 89 days before you start balls rolling to cover your own butt.
These obviously aren't normal times, so you have to be patient.