Cheap pizza oven

[Magicpizza]

Hi guys, I lost/can't find the thread where I posted last, so here goes: A friend of mine is looking to built a oven as cheap as possible as he is short of funds and he wishes to use the oven to sell pizzas to support his family. The firebricks here are really expensive now, so I was thinking about casting the dome using firecement? Any help?

Cheers
Colin