Price of laptops (and probably electronics in general) is higher than what it would be in the US.
For example a Dell Inspiron 15 Touch laptop sells for $499 (regular price) in the US. In Australia it sells $594 and that is with a 15% discount for Boxing Day. It is difficult enough to find a laptop that you can use to play Skyrim in the US for $300. You are going to have a more difficult time in Australia because local prices are higher.
You are looking at a used laptop. Try and search around for a used laptop with a dual core Core i3 / Core i5 CPU that begins with a "3" in the model number like the Core i3-3110m. The "3" means it is an Ivy Bridge generation Intel CPU which will have an Intel HD 4000 graphics core that should be good enough for a mix of low and medium settings for Skyrim @ 1366x768 resolution.
Better yet would be a used laptop with an AMD Trinity A8 series APU like the A8-4550m which is a quad core CPU (although it is a bit weaker than an Intel CPU), but it will have an integrated graphics core that is more powerful than the Intel HD 4000 which should allow you to play on medium settings.