How much is a box of books worth?

The missing box is 2 cubic feet. It is definitely lost never to be found. I have been asked to estimate the value of the box. All I have to go on is the movers' description "books". I have no idea how much I should claim. What is reasonable? I'm afraid of asking too little and having them accept it without arguing, but I also don't want to claim so much that they enter an aggressive negotiation. Should I just submit an amount or should I submit a list of books with their prices on Amazon as backup documentation?

I've been working on a list of books I'd like:
https://www.amazon.com/wishlist/1UZLFAWCS2B4V/ref=cm_reg_rd-upd?_encoding=UTF8&msgid=updated
Is there anything you'd recommend adding to that list?

I don't think I have a "full box" yet, though I might experiment with one of the 2 cube boxes I have left and see just how much space I reasonably have by packing it with similarly sized books.