No idea where you can get them in north bay but the proper reference is UHMW sheets (preferred) or HDPE, you do not want Teflon (it won't hold up). You can purchase these sheets online from a number of retailers. It machines very clean so don't worry about buying short strips and piecing them together or wide sheets and cutting strips. Often you can find sled runners (the kind you put on pull toboggans) on sale. They are also called Hyfax strips, etc.
Here is an example retailer
https://www.ontarioplastics.ca/products/pla...lyethylene.htmlHere is an example runner (hyfax)
https://www.amazon.ca/HDPE-SLED-HYFAX-RUNNE...&sr=1-1-catcorrDespite most of these being advertised as HDPE, they are usually UHMW, either will work but UHMW is preferred.
You can also sometimes find puckboard really cheap, typically it will be HDPE but I have seen it cheap enough that I wouldn't care. If you have access to a table saw you can easily turn it into the width you need.
I sometimes find folks on the usual marketplaces (kijiji, craigs, facebook) that are selling cutoffs in bulk extremely cheap so its worth a search that way. Good luck with your search.
One more thought. Look around for a local snowmobile graveyard/wrecker/restorer. They may have piles of hyfax runners laying around they would sell cheap.
And one LAST thought. Dog sleds (modern ones) use the same runners. They are cheap in the states, much more expensive in Canada (sigh) but maybe you can find some used ones or NOS.