How do I pay?

The only time I ever paid with a cashier's check was to someone with a lot of feedback, who lives in a city where I have good friend who's be able to track that person down if we need to. And I spoke to him on the phone many times. I wouldn't do it. 

Don't do it.

@elliottbnewcombjr , I am sure it was not easy to go through the whole shipping damage issue.  As you pointed out, the insurance is with the seller/shipper and is like a contract between them and the shipping company.  As a buyer, you really have little protection and are somewhat at the mercy of how the seller handles shipping issues, which goes back to feedback and dealing with honest and reasonable people.  Just another risk of buying used.  IMO, big speakers should be strapped to a pallet.

Recruit a guy local to the seller. Search for a nearby high end shop and offer to pay someone knowledgeable a fee (whether or not you end up buying the speakers) for them to go and inspect the speakers and hopefully hear them function. Could cost between a case of beer and maybe a couple of hundred bucks.

Another one I have used is to place the money in escrow with a lawyer and have the gear shipped to them (if the speakers are 6' high and weigh several hundred pounds this may not work). They send the seller a letter saying that they have the money and will forward the money when the gear arrives and has been inspected, the only alternative being to send the speakers back.  Probably a similar cost with the lawyer if they do other stuff for you.

I wouldn't buy from a person with zero feedback without using some sort of escrow.

Nada, keep looking