There aren't enough Melbournians or Victorians here to get a good representative. I think there is probably 4 or 5 on this forum and only 2 other members besides myself who are absolute regulars of this forum. There are other members who live in NSW & QLD.
It is very likely that a physical shop would not be terribly successful as there are not enough professional dancers in Melbourne to sustain it. Most either buy online or buy when they go to Egypt. I am one of those. mainly because the cost of a costume locally is a ridiculous price. I can buy a really nice costume including postage from the online BD store based in the US, for at least 1/2 the cost of what I'd pay here & get a much better selection. If I buy in Egypt it is even cheaper.