For the blue and white stars swap the lady arranging it had an online shop, so she put the postage cost in her shop with our names so we knew which was ours, and we bought it via paypal.
I could probably exchange money for dollars though, if thats easier, since we're planning a trip to America later in the year. Probably have to round up to the nearest dollar though, so as not to put change in.
Just let me know whats easier. Theres a while to think about it yet.
Sazu, UK