Relying on my old fading memory, I don't think a S58T ever operated in Oz due to the restrictions put on by CAA. They did operate in PNG but only allowed to carry freight as it didn't have 2 independant fuel systems, so I'm told.
The S58 & Wessex 60 did operate here but many years ago. The Wessex Mk2 were going to come here from NZ but their CAA stopped it.
Now to find out if my memory is right!!