The constant complaining from international markets (especially the UK) about how "the prices are not fair waaa, waaa" and their only understanding of market costs is based on exchange rates is pathetic.
If that's all they think that prices are based on then it should work like that. Every day, every hour, the prices in the UK Apple stores should go up and down constantly so they have no idea how much one thing will be from one minute to the next.
Forget about the fact that UK prices are VAT inclusive and the US prices are not. Forget the manufacturing, import and transport costs that are significantly different in other countries. Forget the cost to licence software elements and hardware patents ...
let's ignore all that and just base the price on a figure that is as solid as a bag of water.
Or better yet why not buy directly from the US so you can take advantage of currency exchange rates directly? After you've paid your credit card exchange rate commission, the international shipping fees and the customs fees you might have a better grasp of how an exchange rate is a minor factor with the cost of products sold in your country.