Instinct’s recent releases of WordPress E-Commerce plugin (since 3.7.1) include support for shop owners to set prices for multiple countries as an alternative to lumping the difference under postage.

Multiple country-based product pricing levels are managed on the Add/Edit Products page below the Stock Keeping Unit field with a ‘+ New Currency’ link.

Update: Lisa hinted that current support for multiple product currencies is cosmetic and doesn’t affect the checkout process, the real deal is coming in Jan/Feb 2010.