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.
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.