Jemol,
You will need to ask the foreign suppliers to issue a credit note(s), provide them with your Irish VAT number and request they issue new invoice(s) showing zero rate of VAT. You will then be obliged to self-account for Irish VAT at 21% on the value of the goods on your VAT return and provided you are fully engaged in VATable supplies, claim a simultaneous input credit on the same return, rendering the transaction VAT neutral.
The foreign tax authorities will (under no circumstances) repay VAT that was incorrectly charged and VAT has been incorrectly charged in this case so you will need to contact the suppliers.