This has to be one of the most frequent monas people have about PS.
I still say as WA are marketing globally they should have at least 3 versions to download once purchased:
UK Pound Sterling
They know where all the references to the currency are so it would make so much sense for them to take a few minutes to make these versions.
Either that or PS should have the currency in a settings file so its changed globally in an instant.
Just an idea.