Take some really good pictures of some of the rifles then offer up the crate for $10k.
The worst thing that could happen is nothing. No loss there.
If they don't sell then trickle them out one at a time. Take each one down for pics of matching serials and so forth. Use the empty crate for a rabbit hutch.
A buyer might just take you up on the case and save you a lot of trouble. You won't know unless you try.
They're going nuts out there.