Buying through eBay isn't like buying from the shops. eBay warns buyers in the user agreement that they do not guarantee that items sold here are safe, or even that they comply with the law.
Quote: "eBay does not guarantee the existence, quality, safety or legality of items advertised, or the truth or accuracy of descriptions".
eBay passes on some consumer safety recall notices to buyers, but as eBay's money back guarantee doesn't cover motor vehicles they would have no other involvement. Any responsibility for the sale rests with the seller, and with the buyer to make all necessary investigations before buying. eBay is a jungle.