Since my original post explaning the availability of methylcobalamin imported in to Australia, I personally haven't had any problems importing B12 methylcobalamin or lipioc acid, carnitine, or GLA, but i only order one item at a time and all has come through Aussie customswith no problems, they always do open the packet and check inside all of my orders and leave information on it saying that they done so.
However i have learn't by Aussie, that our Quarentine officers can do random inspections on any imported parcels coming into our country which attracts a $48 dollar quarentine fee, these checks are random and indiscriminate, but can happen.

Brian