I too have one of these, Mine was given to T.A. Wilson who was CEO of the Boeing Co. at that time. I have all the paperwork from Colt Arms. They were given in glass top presentation cases inleted for the powder measure, nipple wrench, caps and a parchment rolled up with a leather thong. The parchment is from the Conquistadors event with group photos, sporting events and such. Each side of the barrel is engraved, one w/ aviation symbols, the other with sporting events from the event.
I saw another one once at a gun show and the guy had no idea what it was and I foolishly told him what I knew, I went back to buy it a few minutes later and he had pulled it off his table and no longer wanted to sell it. I don't have a good feel for value, as a collectable mine may be more valueable to Boeing collectors?