Bob, where in the uk does he claim to be from ?
What exactly are you expecting the independent person to verify for you ?
It is possible if you know the town you may be able to persuade him to meet someone from here who is local to him.
I personally wouldn't have a problem with meeting someone for you, but what that proves to you I'm not quite sure.
I have brought stuff from the US in the past and used escrow to ensure my money (and the sellers goods) was safe. It does cost, but better to be safe than sorry...
Send me a message if you like and we can discuss this further, or respond here.