You don't need a replacement especially if it's going to be the same badly fitting item.
The item is not fit for purpose so listen no more to the seller's excuses as you need to receive a full refund, so just proceed this way:
If you are still within 30 days of the item's last estimated date for delivery you are guaranteed a full refund, under eBay's 30 day MBG, Money Back Guarantee policy.
Just proceed this way:
You have received an item not as described, go right of the item in your Purchase History and from More Actions select... Return this item selecting the reason Item Does Not Match Description or Photos.
The seller needs to accept this case within 3 days and refund, if they want their item back first , they need to pay for that fully tracked return postage, then on receipt of their item they have 48 hours to refund you. If they don't , need to escalate the case, ask eBay to step in, and they'll force the refund.
Never listen to any excuse or promise from the seller to close the case early, and do not forget to escalate.
@stainedglass
