I have been playing with myus.com which is a US re-mailer and gives me a US address in Florida. This allows items purchased from US companies that only deliver to US postal addresses. This costs about $60 a year which has already payed for itself when buying high cost items.
The price of a mid-range / cheap goods turns out to be only slightly cheaper (R100-R500) when purchasing them locally. High end goods seem to attract a very high margin locally so you can easily save up 50% of the cost by purchasing from overseas when taking advantage of exclusive US discounts.