Hi Nicky
I know the Canadian health care system is insurance based and differs between provinces. Dental treatment, ophthalmology, and prescriptions are all private and not covered by the insurance, but I don't know about regular blood tests.
We were invited to stay with relatives in Vancouver a few years ago but I was unable to 'buy' the Enbrel there and couldn't take it with me because of transportation problems so we were unable to go. I guess you will need to take a letter from your doctor with your diagnosis and current medication (and a two month supply) and then get in touch with a doctor as soon as you arrive. Some of our meds aren't available in Canada but they do have others that aren't licensed here. Presumably they would organise this for you but it may be different.
Wintersports and existing conditions is a difficult one! My experience of finding even holiday insurance for two weeks in Europe has been fraught with worry because of the surgery I've had, the treatment I'm receiving and the surgery I'm waiting for!!! I've got insurance but it excludes anything related directly or indirectly to the RA; you can ask for its inclusion, most will do it but at a premium. Wintersports? With RA? Hmmm .....
As Doreen suggests the Embassy will perhaps be able to advise.
Sounds a fab opportunity and I hope you are able to get it all sorted; gosh only a month to wait, how exciting
Lyn x