Best of British luck to you Dub, but as a small player I doubt you can get a start in the game. A couple of years ago I was asking the same Q. I wanted to refinance my mortgage in US$ (a Gnome Loan but in US$) but it seems I would have had to add another zero before it had a chance. Anyway, I think the best of the A$ appreciation is behind us. While the Pacific Peso may be the flavour of the month, nothing goes up for ever. Now if we can find out how to buy Ag & Au futures denominated in USD there may be a quid to be made.
BTW I commented on the rise and rise of Redback yesterday. Must be one of the best performing golds.