I think you're right. I searched the internet for hours/days/weeks and those were the only ones I found. Then I spent many more hours looking for a supplier/dealer in North America (there aren't any!), then many more hours, and emails, to England to find a supplier willing to ship to Canada."
In fact, according to a Quebec, Canada highway safety code regulation that went into effect on December 15, 2014, only tires that meet the 3PMSF standard are considered to be acceptable snow tires for use in Quebec. The law specifies the winter months there as ranging between December 15 and March 15 each year. Winter vehicle requirements may differ by region, so it’s worth familiarizing yourself with what’s legal in your area before you go tire shopping.
While you’ll find many motorcycle tires that bear M+S designation, the Anlas Winter Grip Plus is one of the only (if not the only) motorcycle tires with a 3PMSF rating as of January 2022. "
Ask RideApart: Are There Motorcycle Snow Tires?
Anlas had another winter tire, too, but seems to have been discontinued. Can't remember the name now.