Well mjl, it sounds like your problem is mostly resolved.
For anyone who wants to listen, there is plenty to say for being able to trust a man's word and doing business with a handshake. The problem comes in that with a complex item, such as a musical instrument, it always pays to get it in writing. If the term 'contract' bothers you, then call it a letter of understanding or just sit down with the guy and as you make up the order, write it down, then send a copy. This saves a whole lot of confusion over details. Especially over the course of months (in my case days), details can be forgotten.
If seller doesn't take it upon himself to write it down on a shop order, or whatever, you as the buyer can write it down and make sure you both have a copy. Tell him you own memory is not what it ustabe and you need to write it down so you don't forget. You might just save a friendship. If the worst happens and the luthier does pass on to his great reward before deliver, how are his heirs supposed to know what you two agreed on. You can't be mad at a man for dying, but you're still out your hard earned bucks.
"If you've got time to breathe, you've got time for music," Briscoe Darling