Only 13 Air Raid games exist for the Atari 2600 and one of them is up for auction on ebay right now.
The last Air Raid sold in November 2009 for $2,850 and this auction is already up to $1,300. Will it end higher than the previous price? My guess is it will. Rare games seem to be more popular now after the Stadium Events madness.
UPDATE: The seller ended this auction and posted it again WITH THE ORIGINAL BOX!
The bidding is already up to $4,300. This is the only Air Raid box I have ever seen. I'm not sure if its the only one ever but there are probably only one or two. Here is the new Air Raid auction.