Sorry to hear about your supply problems - even though it's a bl**dy big island! Seems like the Continent of Oz is little different to here in the UK. Once upon a time, there were many model shops, most stocking virtually everything (within reason). Most of the bigger towns and cities still have some good outlets, but some, particularly the smaller concerns, are, to an extent, at the mercy of the suppliers, and their 'minimum order' policies and similar. Some (very) long established shops have now gone, bought out by 'High Street' chains, which tend to be more of 'this is what we have as it's the latest product' sort of place - not a lot of use tio the serious modeller, apart from the occassional 'good deal', normally stock clerarance sales. I was horrified to learn recently that, what used to be my local shop, where I was born and brought up, has been 'taken over', and relocated, after almost 100 years of trading!!
Like many of us, I now have to rely on mail order for a great number of items unobtainable locally, even to 'special order', so thank heavens for the Internet! Before the creation of this fantastic system, mail order could be prolonged, and hit and miss!
Just a thought for your Natural Metal Finish, if you can't obtain Alclad. Somewhere here in the modelling section, I posted a piece on Bare Metal made easy, which might help you. Of course, you might prefer other methods, but it's worth a look.
Cheers,
Terry.