Buy your tyres up there .There are several dealers who actively support long distance tourers and their prices are reasonable when you consider the geographic location .There is no point lugging tyres for thousands of miles.
Don't buy tyres in Canada ,they are ridiculously overpriced .
Start off with fresh rubber to make sure you can get there ,then swap ,if you wish ,to TKC's if you are doing the Dalton or Dempster .
Tourances ,Annakees etc are also available.
It might be best to email the dealer to put them aside for you .
Blessed are the cracked, for they let in the light. - Spike Milligan
"When you come to a fork in the road ,take it ! When you come to a spoon in the road ,take that also ."