I don't know where you are situated, I am in Brisbane and after surgery was left with one B size breast and one D size breast. The solution I found was a partial prosthesis, it is Amoena brand, and was fully refunded by Medicare. There is a shop which specialises in fitting these, they also have the prostheses for swimwear. The lady there who does the fittings helped me with the Medicare forms, also advised that some health insurers give an allowance towards bras. I can let you know the name of the shop if you are interested.
I am interested in the shop you went to please as i live on the sunny coast so brissy inst that far for me. I will go one day after my mastectomy wich is on Wednesday. I also love that you mention for swimwear as thats been one of my concerns.