Nothing can be done through eBay now as the transaction closed with a refund.
The repayment can now be done sending a Friends and Family payment through PayPal, or the seller can send you a PayPal invoice for the amount. Or pay by cheque or bank transfer.
One tip, if PayPal is used email addresses are required, make it very clear in eBay messages the purpose for asking for the email, so it cannot be mistaken for the beginnings of an off eBay sale.
