Uhm. Why are you losing 2-4 $ on an EU sale?
Pricing is US based and that means they are displayed without taxes. If you ask for 20 $ and a customer from the EU pays, there will be VAT added to that 20 $, not deducted from the price you asked. So that customer would pay 24 for your 20 $ item if vat is 20%. It is called value added tax for a reason.
Or am I missing something here?