Series 5 also the same price.
Also check DVD Box set for series 1-4 for $58.49
http://www.ozgameshop.com/box-sets-tv-dvd/doctor-who-complet…
Unfortunately if you purchase individually the code won't work for $5 off as it's 1 cent under T_T.
Be warned as this works only on a region-free or region B blu-ray player.
It's a good price but tbh I didn't enjoy this season, it felt all jumbled up. Perhaps season 5 spoiled me.