Seems to be a decent price on this, it's currently $89.95 on PSN store, the only other price I could find was $68 at EB for a pre-owned copy.
Add another $22ish of stuff for free delivery with Prime.
Not sure why it's showing up as good deal games, but the cheaper option is sold by Amazon US (click the "New (8) from $27.17").
Amazon US via Amazon AU
Minimum $49 with Prime for free shipping