HI James,
If you choose to come to Ontario. Lake Country Airways is a great place to learn floats:
Lake Country Airways: floatplane training, endorsements, float charters and rentals
Ontario does have a shorter float flying season than BC, here it is Late April to October, though I did land in the water two weeks ago, and again today in the same place, on the ice!
BC is beautiful, and there is excellent float training there too. Ontario probably has more good flying days, and more stable weather in the summer. Lake Country Airways is not far from Toronto, where you would have a number of options to do multi training.