These are common items in US.....
Go here...
http://www.mcmaster.com
Here are the "nuts" and "nipples" that are the correct fittings for hose ends (US)...
Nuts ...#7919A3 (oxygen) and #7919A4 (fuel)
Nipples ... #7919A1 ( 1/4 inch hose) OR #7919A2 (3/16 inch hose)
IF you do not have facilities to "crimp" ferruls you will need to consider clamps
You can just look on page 3301 for the parts... Also there is "lots" of "stuff" on a few pages before and after this one...
These are common "welding" supplies in U.S... So you probably need to find a US supplier that will ship down under...
Dale