yeah I kept looking at Adorama and B&H and their own site and it was always more expensive than Amazon Canada... and I'd have to pay duty/taxes on top of it.. found it weird, but taking savings where I can. Unfortunately they won't have stock until Jan 20th... but honestly for most things my SD card from my 80D has been sufficient so not in a rush.
I picked up mine on July 28th (before the R5 was released) for 379.79 USD on Amazon Ship/Sold by ProGrade. At that time I figured the demand would go up for them so wanted to get ahead of it. However the point is, we might see them again at <400.