Hello,
I've just had a good experience with www.wheelcarrier.co.uk. They are cheap but reliable and offer what I thought was a great service when collecting & shipping an exhaust, but as the name suggests, they specialise in Wheels / Tyres. Their website is not the best but they do respond quickly to emails and will offer a phone number to contact them on should it be requested.
Under distance selling regulations, the seller has to issue a refund if the item was purchased via Buy it Now or Second Chance Offers on eBay, if the buyer requests it within 7 days (or longer if the seller accepts refunds). If it was a bidding style auction, then the rules are a little different. Sellers can request that the buyer pays towards the cost of returning the item, but only if that is made clear before the transaction takes place.
If you buy as an individual from a business trading on eBay (or any other online marketplace for that matter), your sales are subject to either the Distance Selling Regulations 2000 or the Sale of Goods Act 1967. I don't know much about wheels and tyres, but I would question if the courier had caused the damage to these items, and I would question a seller who sells online and believes themselves exempt from DSR's!
I would request a refund, perhaps paying for the return yourself (to meet the seller half-way), rather than taking the hit for the repair!