The floats may seem like something more but they are just parts. No different then buying a set of wheels or even big tires, sometimes different people try and make a big deal out of floats. Don't make a big deal out of them and move on with the installation. The Canadians and United States have an agreement to honor each others STC and Canadian Approval so as long as the paperwork is in order (US 337 or Canadian equivalent) everything should be good.
If you need more information from the ones in the know, call Kenmore Air in Seattle. Kenmore is EDO Floats now and they fly daily scheduled flights in and out of Canada every day.http://www.kenmoreairharbor.com/maintenance.html
The only advise I can pass on is don't ask the FAA or Canada Aviation guys for advice.
Klaus Marx - Piper Pacer Pilot
Juneau, AK & Wenatchee, WA . . . . . . Click on Link Bar to view the 'non-profit' group.