injectable B12 isn't a prescription only medication in Canada - you should be able to get it from a pharmacy without needing a prescription so no need to order, unless there is a shortage in Canada at the moment.
sourcing from canada if you are in the US can sometimes be difficult as the US Government has tried to place restrictions in place on supplies of script only medications. However, it would also seem to be the case that injectable B12 is only covered if it is being supplied for medical reasons in the US as well as the UK, which means that you can get it from 'slimming clinics' - know some US based members of the forum do that.
Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.
Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.