In at my local Bunnings in Bendigo (Epsom) and saw they had the gas conversion kit on sale. A steal at $35. Comes with the hoses, connectors, regulator, and ball valve. Note This is not the kit with the bayonet fitting, that's still $99.
I made the switch for my 6 burner jumbuck a few years ago and haven't looked back. No notable loss of heat and no stuffing around with gas bottles. Just in time for summer, no idea if state wide, about 12 kits that I could see in stock.
It's recommended to change your BBQ jets to a bigger size for NG. People have drilled the holes out bigger if you can't find new jets (me included). Do your research first.
Good deal but probably store specific? Doesn't appear on website?