I would tend to disagree with checking ebay for one reason. I do believe the price is a lot of times skewed a little bit due to the fact that there are factors involved in any auction such as the "I take it personally if I am outbid" factor, and some people pay way more than they would otherwise just due to the fact that they cant stand the thought of someone else outdoing them. The way you describe the truck to me seems like it needs the bed boards replaced, the tailgate reinstalled, which, if its not on the truck, where is it? and was it stored carefully? So there may or may not need to be some repair work done to the tailgate, And the whole deal about how many miles are on the engine since it was rebuilt thing, I dont know how much of that to believe unless they have receipts when it was done and they can prove that, it really has no effect on the truck. More questions to ask yourself, the interior is original, is it in nice shape? How much work will it require to get it in respectable conditon, or at least a condition that you are ok with. As far as the body goes, it sounds like it is real solid, which is a plus, but it does need repainted. From the sounds of things, it is a real good find, and one worth picking up, I would probably not pay more than $5000 personally, based on the information you provided.