It's a very rare item, and it's value is really based on it being intact and in the SW.  I would anticipate the value being about $200-300 in today's market, but since they really don't come up for sale much, it difficult to assess what it might sell for.

Great!  If you want to maximize the potential sales price, list it as an auction, with a low starting price, and let the market drive the final sales price.  Trust that it will find the maximum price.  That's the only way to see how high it will go, since there aren't any recent sales to base a starting BIN price on, and you don't want to sell it for too low, or list it too high, and scare off potential buyers.

Definitely describe it well in the auction and post the listing in The Acaeum Classifieds.