Grado might be difficult to find outside the United States. I'm pretty sure their distribution is limited in this regard. There are however authorized dealers of Alessandro headphones (they also ship worldwide from their website) which are re-branded Grado's. Same materials and transducers made by Grado.http://headphones.com.au/pbrowse?catID=1&brand=Alessandro
I own a pair of Alessandro MS1 and thought they sounded good until I compared them to other headphones directly. My biggest problem with Allesandro and Grado in general is they don't scale well with volume. You can also see the problems in the frequency response. They have wonderful detail at low volume but as soon as you crank them up I can hear the inbalance in the upper midrange and they become fatiguing very quickly.
That's one thing I quickly found out when I purchased a pair of AKG 271 MKII and AT AD700. They maintain their balance at all volumes. Nothing sounds offensive or sticks out when you crank them up, everything just becomes louder. No listener fatigue.
Since you live in Australia and prices are more expensive I would probably look at these headphones in your price bracket. From my experience I found diminishing returns once I reached the Beyerdynamic DT880. http://headphones.com.au/psingle?productID=5http://headphones.com.au/psingle?productID=178
This right here is a textbook, ideal frequency response for a headphone. For proper tonal balance, headphones shouldn't measure flat or be elevated in the upper midrange and treble.http://graphs.headphone.com/graphCompare.php?graphType=0&graphID=3221