TSN would want to renegotiate their deal and the league would make less $$
Only way it has a chance to work if for the league to create more content. Only way to do that is either increase the regular season which is a hard sell for the players or expansion.
If the logistics of US expansion could be sorted out (which I don't see happening), the games with the US based teams could be offered on a separate PPV since they'll be of lesser interest from TSN or any other Canadian network