Who in Canada or the US (preferably in Canada) manufactures plastic
wall-mount hand cleaner dispensers?

Do you really mean manufacturers, or will distributors do?  If the
latter, check out http://www.1stopvacuum.com/html/soap_dispensers.html

Or, you might try Wood/Wyant--not sure if they manufacture or just
distribute.  See http://www.woodwyant.com/english/page.asp?page=100268
and http://www.woodwyant.com/english/page.asp?page=100278