Since the UK and Australia share the same DVD and Bluray specs, then the answer is yes, your UK bluray will certainly be able to be played on your Australian player.
If you are interested in buying any of the many Blu-rays exclusive to the international market you should consider purchasing a region-free Blu-ray player. I recently purchased 2 Toshiba region-free Blu-ray players and the were $136.00 each. They will play any region DVD and Blu-ray (A,B,C). International Blu-rays like Strike Back are transferred in their standard 1080i/50. The USA standard is 60 hz. Many region 1 Blu-ray players aren't designed to convert the 50 to 60 so the LCD/Plasma can't display the image. In the past many of the Vizio's and other brands were multi function LCD's meaning they could convert PAL to NTSC and 50 to 60. Today I think most LDC/Plasma are specifically made for North America so you need a region-free player that includes a video converter. To find sellers just Google "region-free Blu-ray player".