The Principe de Asturias is a good design for supporting somebody else in combat, but its much too small to be able to operate on its own. I can't see Australia or New Zealand being good with that, particularly if they are facing greater threats from Indonesia. If that's the threat, Australia would be better off spending their money on lots of strike aircraft (F-111s or TSR-2s or perhaps even Vulcans or Victors - or hell, maybe even a squadron of B-1s later on) and lots of aerial refueling tankers for fighter-bombers like F-4s, and New Zealand on frigates, OPVs and submarines, along with enough fighters to protect itself and a handful of support aircraft - tankers to give the fighters longer range and AWACS to improve their effectiveness at air combat.
Both Australia and Canada (and Britain and France, hint hint) are gonna want something that can handle its own fight if they are gonna spend money on carriers. The Invincibles go out the door here for the same reason as the Principe de Asturias. That means at least the Clemenceau would be the option to start at. A modified Iwo Jima or Tarawa is a possibility, but again helicopter carriers aren't gonna do fuck all as fighter carriers unless you get capable supersonic VTOL aircraft, which is possible but a long shot. Ideally you'd start with something Charles de Gaulle size (though without its nuclear power, obviously, too pricey) so that it can carry plenty of fighter-bombers and the support aircraft they'll need to be able to put up a real fight in a medium-threat environment, as the US puts it.