Australia with Canadian parties

[Platypus]

I suspect the Liberals would be a very, very small party, in permanent coalition with the Tories, and taking seats like Wentworth and Kooyong. Kind of like the Nationals, but exactly the opposite. The NDP would be the primary left wing party by quite a lot.

The Tory/Liberal coalition would be strong, but the NDP would govern very occasionally. Probably lots of 15 to 20 year Tory/Lib governments, followed by 6 to 9 year NDP governments.

[Platypus]

Canberra would be battles between the NDP and Liberals, the Tories wouldn't even try. NDP would likely win both HoR seats, and the senate would split between the two.