There's a 4G model too which should work on more networks.
It's a Europe-based company so I assume they're mainly looking at European frequencies, but they have a page about US providers if that's any help? (https://opis-tech.com/en/support/documentation/telephones/440-byod-us-cell-phone-service-provider-considerations-for-the-opis-60s-mobile-4g-and-pushmefon-mobile-4g)
@drimplausible
ALSO: There's this page from the 2G model which includes a section on Canada:
https://opis-tech.com/en/support/documentation/telephones/400-opis-60s-mobile-network-operator-considerations