Usually bigger countries like USA and Hong Kong sell their camera cheaper due to economies of scale and more competition. Unfortunately, in Singapore, cameras (and other hot-selling electronics) are often priced higher than the countries I mentioned. However, you may need to take in consideration the local taxes and duties you have to pay if you import them.
I think its Hong Kong or USA (now USD drop). I have also heard that if you hand carry the box (inside got camera) you must declare, One member point out that take out the camera and put into your camera bag and the box in your luggage (checked-in). I think warrantly also a problem, no idea about that tho.
the next question is the difficult one. where in that country can you get the cheapest DSLR?
it can be that it is cheaper if your friend knows the photographic retail market there well or if not, they got to hunt high and low for that price with a lot of inconvinience. on the other hand, it can be more expensive if your friend are just buying at less inconvinience from department stores.
ultimately, you got to try to find out the market pricing AND availability at SPECIFIC locations, including its tax and so-on. then you got to see whether it is worth the hassle. it is less complicated if you are going there yourself, hunting around on your own, asking what you need to know there, and deciding on it.
anyway, forget abt australia for cheaper electronics. things are neither designed or made there, nor a large market, so it won't be cheaper.