lots of factors go into it (pin, top weight, how much it weighs), but the most important aspect is this....... did people want it when it was released, and do people want it now?
The "big blue" series wasn't a game changer, but it wasn't a bad series release either; I'd think that (if its 14 or 15 pounds with good specs) that you should be able to get around $140-$175 for it.
If it was an original blue hammer, or even a 3d offset solid/pearl, then you'd be talking a lot of money. A big blue pearl is nice, but not enough to get "overly" excited....
Sorry to pop your bubble