Stussy,
Most Far East and Middle East countries will accept an Australian licence with little more than an Air Law exam. More important than the licence though will be hours, post Commercial licence and how you hope to attain them. The easiest way to find individual conversion requirements would be to contact the local Aviation Authorities in the country you are considering for better information. Run a search and then email for requirements.
All countries that will allow easy conversions from other licences are normally bound by the companies operating there that are looking for experienced people to fill vacanies. So as a result they are looking for people with thousands of hours.
If your intention is to train cheaply and immediately return to the UK for employment then ultimately it will take longer and cost more. As wierd as it sounds, with a bare licence only, a fair amount of extra training will be required to put you into that countries ways. If your intention is to go to a country where you are authorized to work and to gain your first foothold of the industry then collect licences as you travel the world working then this is possible.
Don't go to a country to gain their licence without work authorization then hope to jump into a position in another country as that won't happen and will cost you more in time and money.
If you are fixed in your goal of training abroad, my advice would be to decide which country you would like to train in (Australia, US, Canada or South Africa) gain work authorization and expect to fly there for a minimum of 1000 hours or if possible to ATPL(H) level before you even thought about converting to another licence.
JAA currently doesn't give any dispensation to holders of foreign licences (but this could change) so expect to have to do all JAA exams if your ultimate goal is to return to the UK. If this is the same sylabus as Australia maybe a better solution is to gain the UK helicopter exams (good for three years from completion of last exam) before you head off to Australia leaving only a flight test when you return to the UK with your 1000 hours.
Hopefully that helps.....
PS Don't know if the Aussie market for newly qualified helicopter pilots is particularly strong.... Maybe that is another question you should ask.