The reason would be is that they don't get asked for them that much. I think what she pulled out IS what you need, they are 215mm x 85mm and there are 3 layers. The top piece of paper is light brown and white and the 2 receipts under - one is blue and one is yellow. You keep the yellow bit of paper and the PO keeps the blue. You send off the top piece of paper. You ask for X amount of US$ and they convert and add a commission of AUS$8.65.

They then fill in the first line: To the order off - Pinball Recource
The second line reads: Sender's name and addrress - Rob Gulfstream, 123 Fake Street, Sydney, NSW 2000, Australia

I just checked the last receipt just sent to PBR and it clearly stated across the top INTERNATIONAL MONEY ORDER. Along the bottom left reads 'Western Union Money Order is a service mark of Western Union Financial Services'