I looked into a USPS claim once for some glass items that were broken when I opened the box. The clerk at the local P.O. said I'd need the box the item was shipped in and all the packing material that it was wrapped in and protected with. Then it would take over a month or more to reach a decision and settlement.

Hopefully, if it comes to that, the seller still has the box and packing material. If not then they are probably "sorry, out of luck".