Seems that blueberries only got to Oz in the early 70's and are only now becoming affordable.
This is one of Gabriel Gate's excellent. Low-fat recipes. It was first published in his book Smart Food (Anne O'Donovan, 1989) for the Anti-Cancer Council.
Blend 500 g blueberries to a puree with the juice of 2 oranges and 1 lemon.
Strain the mixture. Stir in 1/4 cup sugar. Beat together 1 cup low-fat yoghurt and 2 tablespoons low-fat milk for about 5 minutes to lighten them.
Add 1/4 cup of sugar and beat for a further minute. Gently combine the fruit preparation with the milk and yoghurt mixture. Either freeze in an ice cream maker or put the mixture in the freezer in a bowl and as the mixture hardens, whisk it two or three times. When it is too firm to whisk any more, it is ready.
From "Raw Materials" by Meryl Constance, Sydney Morning Herald, 1/5/93.