Get Prawn Supreme's for $7.95 delivered. Cheapest I could find for any delivered pizza from Domino's.
You can also swap up to 2 toppings out for others, plus change sauce, without paying extra. Has plenty of toppings, so it gives you a bit to work with in terms of swapping if you don't love the pizza (the original toppings sounded like an odd combo to me).
Tested in NSW, QLD, TAS & VIC, think it should work in all states.
Bear in mind you still need to meet the minimum delivery cost of $21.90
Enjoy.
Do you still only get two prawns per pizza?