Its hard to get them across the border as many sites dont ship to canada. There are a couple canadian-based sites but ive noticed they are more expensive as they specialize in 'fancy' seahorses. I looked into getting some dwarves and might still do it, but i need them shipped to washington where i can go down, pick them up, and cross the border with them myself.
Ive never really seen the dwarves up here, but some pet stores have them occastionally. I know Pet Gallery on Denman had them but they are closed down now. You might want to contact some local LFS and see when they are getting more in, or ask to specially-order some for you.
-Diana