Dunno if it applies here, and perhaps you already know this - but can you return them to the retailer under the distance selling regulations?
https://www.gov.uk/accepting-returns-and-giving-refunds
"You must offer a refund to customers if they’ve told you within 14 days of receiving their goods that they want to cancel. They have another 14 days to return the goods once they’ve told you.
"You must refund the customer within 14 days of receiving the goods back. They don’t have to provide a reason."