A FR 38 is equivalent to a UK 10, , IT 42, US 6

There is a slight stretch not much.  I find that a size 10 AUD would have slight trouble putting it on  especially around the hip area, so I would recommend a size 8

Am selling at a reduced price being the item is floor stock and has been tried on only not worn.  Tags are still attached.  There is a slight tear inside the top at a seam where it can be easily stitched back or left.