Originally Posted by
nobody
honestly, these are rare & don't come up very often, so pricing them is rather difficult. The people that know about them, most likely already have one, and the people that want one, generally don't have a need for them. Since it was made before constant air, constant air turned it into a niche item. And where you can use it, it is either outlawed because of the check valve or again out teched by constant air. So it is a niche of a niche.
Price it what you think it will sell for(or what you're willing to let it go for) and put it up on ebay. You will get looks here but no serious buyers(prove me wrong!). And blame agd for making something too good, like the 6-pack, but worthless.