If you have home owner's or renter's insurance, check with your agent about a policy to cover damage in transit. There's always Lloyd's of London, but they ain't cheap.
Finally, if the party who is shipping doesn't have the ORIGINAL boxes or crates, spend some money to have a crate made for large speakers. One per box, and both strapped to one pallet if they'll fit, separate pallets if not.
Finally, if the party who is shipping doesn't have the ORIGINAL boxes or crates, spend some money to have a crate made for large speakers. One per box, and both strapped to one pallet if they'll fit, separate pallets if not.