Looked around for a 30-day prepaid non-Boost sim with at least 5GB data (for churning purposes) and the best I found is Lebara 8GB $7.45 (until 31 Oct).
I used to depend on Kogan but can't see any deals at the moment.
If you know of any non-Boost 30-day deals would appreciate a heads-up.
Thanks.
Take a look at the Coles / Woolies catalogues (sometimes you're better off looking in store as not everything will be in the catalogues).
There are usually some 30 day sim deals at the $10-15 mark. Amaysim and Vodafone usually have some deal going at the supermarkets.