Hi alasearwax,
I’m guessing that you are referring to something without some sort of flame retardant chemicals added to the foam.
As for some foam suppliers with which I am familiar, you may wish to check out this list of companies of which I am familiar that ship in/to Canada and see if they have anything appropriate for you (Memory Foam Comfort might be a good first call, as they may be able to supply you something not listed on their site or have good advice). There is also a list of different component suppliers here and some of them ship to Canada. Your best luck may be with upholstery shops. This article, while for the USA, lists some foam suppliers for furniture which I think might be worthy of investigation.
Phoenix