UPDATE (23 September): The building has been identified. Thanks to those who helped us identify it.
It is the old Marble View church on Eyre Peninsula – it was just south of Cummins. In its life it was a Methodist church, a Lutheran church and a school. It closed in about 1960
We don’t have much more information about it. If you do have something that we could add to this photo, we would love to hear from you.