How did he set the price on them? Just guessing or did someone tell him what to charge. And - have you run the box codes? If I was to spend $500 on pre-embargo's - I'd want to have them verified by a third party.
But given they fact that they are unsmokable - I'd give him $150 for the box simply as a collectable - I mean heck, I got other worthless things that just sit around collecting dust that I paid more than that for -
Ron