From the 2008 Bouncedown magazine:

De Boer 188cm (6'2")
Richardson 179cm (5'10 1/2")
Cockie 182 cm (5'11 1/2")
Ballantyne 174 cm (5'8 1/2")

I'm not saying that they are gospel figures, but I think I would tend to believe a West Australian magazine rather than a Victorian one!