Where would you expect the supplies from an electrical wholesaler vs a hardware supplier are manufactured? As you say they have to comply with Australian standards.
I checked with an "electrical contractor" relative of mine who said most mainstream electrical fittings manufacturers have a "generic" brand sold through hardware outlets and then they sell their "brand name" products to electrical wholesalers and onto electricians, who are passing on the cost with a mark up, so it is the total cost that is important to them. He said think Coles and Woolworths home brands as far as quality goes as they usually come out of the same factory. The advantage of an electrical wholesaler to a contractor is the greater variety and the immediate availability of bulk supplies.
Anyway, the question was where to get USB enabled power points and I think that has been answered.