Tesco's do a two pack of pizza base mix that you make up yourself, each base works out to 10 syns each, high but as long as you only put free & HEX toppings on then it is a pizza for 10 syns and it tastes nice too - mine made a 10 inch base by the way.
someone on here used an asda HEXB wholemeal pitta, I know you've done it now but other options are always good, also a woman I used to go to group with used to use mash potato
honestly just use the asda wholemeal pitta bread as the base, cut it in half, and put on your passata and toppings, as the asda wholemeal pitta is a HEB, quite a few people on here have done it also. xx