These two appeared at first to be dirty, but on further look, and in the ( a tad blurry!) under wing shot, it appears the feathers themselves are a dusty pink all over. Images beside other corellas and Galahs for comparison.
These appear to be the same two I photographed at Hawker College on 9 July (Cacatua sanguinea (Little Corella)). Obviously though, more than two corellas as you have suggested. Two with pinkinsh feathers but I counted around 30 corellas in total. The flock seem to frequent Hawker College.
@AlisonMilton ah yes! Good to know. Seems they are enjoying the area :-) The two pinkish ones were 2 of 4 Corellas in total, with a flock of Sulpha Cresteds ( about 45)