I've seen the signs sell for over $1000 on eBay. There are those among us who know no shame when it comes to bidding to win
. Now that you've let the cat out of the bag, chances are the price is going to soar. The nice thing about this auction site, they seem to discourage last second bidding by extending an auction if there are last minute bids ... that's cool.
Its a fluorescent sign, and fluorescent lighting, like sunlight, makes plastic very brittle over time. If this 40 year old sign has been used (illuminated) during its life then the white plastic is probably very brittle, very easy to crack, therefore the seller will have to package the sign very carefully to prevent damage during shipping. The sign needs to be held firmly in place inside the shipping box by the aluminum frame so the sign can't rock and so nothing can contact the white plastic.
When I purchased the same type of sign for the Pantera International office I made a multi-day trip to the owners home so I could transport it myself. So the price of our sign included the price of that trip (food, gas, lodging).
-G