They should have realized their mistake right away as soon as they went to order it from the distributor. And to not contact you and leave you waiting ! No way. The owner should of accepted his mistake and made good on his promise, especially since you have been a long time customer. The loss he would of taken could be a lot less than the missed business in the future.
Had this happen to me with a car purchase. Called twice to confirm the price so I could get a cashiers check. Went to pick it up and "Oh we made a $1000 mistake" Almost called the cops as they wouldn't give my deposit back. We finally agreed to split the differance and I also got lifetime oil changes with the car. Went there numerous times when I was sitll in NJ for the oil changes but never used them for any other service.