Catholic church, Bungonia. Its certainly not the prettiest of churches, but apparently its the oldest Catholic church in Australia, going by the following info I found:-
Bungonia has two important churches of which St Michael's Roman Catholic church - the oldest Roman Catholic church in Australia - is the most interesting. It was opened in 1839 and consecrated by Bishop Polding in 1847. It is hardly a handsome church being, made from cement-rendered random-rubble. The town's attractive church is the Christ Church Anglican Church (1893) which stands on the opposite hill (my shot from a couple of days ago)
I was thinking along the lines of Susan. Perhaps the interior absorbed most of the building cost. I know Catholic churches can get somewhat ornate. Nice catch!