In the past, I was able to receive partial 
payment for a cel I had bought framed.  When the 
cel arrived to me, the glass was shattered, and 
the cel had been badly scratched by the shards.  
I filed a claim and was awarded enough to cover 
the damaged frame, and the devaluation of my cel, 
without actually having to surrender my item.

Check into this option.  Get a professional 
opinion about what the art is worth now, vs what 
you paid for it, and file a claim for the damage.

Hope this helps!