Can't see that it's a scam. Many TRS, Top Rated Sellers, are able to buying large numbers of books at discounted rates, the big sellers can always charge less than your average Private seller.
Sounds like a bargain if you are after one of these books, check also the seller's feedback before buying see if other buyers were happy with their purchases.
End of the day, if you receive an item not as described, you arre guaranteed a full refund under eBay's 30 day MBG, Money Back Guarantee policy here:
https://pages.ebay.co.uk/ebay-money-back-guarantee/
@judetheob
