Update 2: durd0008 says cheaper again: "$19 at Kmart for the DVD and will also be $19 at Big W starting Thursday", see comment below for link to BigW catalog.
For those who didn't already buy the Blu-ray for $32 in the recent offer, Target have the DVD version for $20:
If you don't have a Target handy, Coles also have it for $23, at the bottom of page 29:
http://www.coles.com.au/catalogues/weekly/next/c-qld-met/ind…
I was looking for this about two weeks ago, and I have seen it on Amazon UK for the equivalent of 24 AUD. It's even cheaper at Target and Coles, and will presumably have the correct region code for Australia. And you can have it now, rather than waiting for delivery!
This deal originally was for the Coles offer, but dqtl74 found it even cheaper at Target. Thanks!
Sorry, I don't think any single movie DVD is now worth over $20…