XSFNRG, I hear you loud and clean. I've had a raw dealing or two but not the magnitude you have described. It will be probably one of the most important lessons you learn in life. Also, the best thing to do is move forward.
Now, since this is the Welcome Centre you will probably won't get much exposure or answers to your questions as not everyone comes through here each time they visit. That said I'll give my opinion.
I see where you made a post back a few years ago so I take it this is the same truck you were working on then. It would be nice to be able to continue the project and finish it in spite of the set backs. Many of us have big set backs to just maybe not the same situation or circumstance.
You can order a vin tag plate and stamp it yourself since there is nothing illegal your trying to do. Get one, stamp it, and install it on your truck. Heck, I'd even rough it up a bit and let it lay out in the weather for a while.
Since this is also not an official "for sale" post I am not going to move it to the Trucks for Sale Forum.
I appreciate the "full story" but the truth is if you want to sell it, post it in the Trucks for Sale Forum, with the price, and also continue the avenue you mentioned like Craiglist, local paper, maybe even Hemmings? If you've had it for sale before and no one inquired then perhaps it is the price, or it may be because its a 3/4 ton which, while a lot of them are out there, it is not the most popular like the 1/2 tons.
If you can get this truck, running/driving, with relative ease then I'd do that as a running driving truck will sell much sooner or you may decide to keep it? The vin tag situation, at least to me, is no big deal. Order one, stamp the number on it and move on. That's why they make the tags in the first place.
Then, if you would like to "vent" or tell of your journey, visit the Greasy Spoon Forum and they will listen to you there.
You bring up a lot of good points. I try never to pay for service I have not received. I learned the hard way to.