I don't think it's a no-brainer that you'd legally have to pay either amount (though this is contentious). With regard to the cash games, it is probably 50/50 depending on how long you've been playing and supporting yourself, etc. With regard to the tournaments, a similar, partly independent legal inquiry might be entertained. If you PM me, I can give you some more info about these questions.
If you were to pay, it would be at the applicable marginal tax rates. There is a useful income tax estimator here:
http://www.walterharder.ca/T1.html The full rocket would be a little north of $48k.