I know what you said. They are MANY people who received the Wanderer track when the event was going on and put it in their box. Now that the other rare one's are dropping freely, many of those folks have finished their boxes. In my guild alone, there are at least a dozen people who have completed 1-4 boxes now that the gears are easier to get...ALL of those boxes already had the Wanderer in them so they are complete, just like yours. I stand by my guesstimate.
Now, if you DIDN'T have the Wanderer because you weren't around for that event, your box may be worth more, but those people can easily get all the other gears to finish their box EXCEPT the Wanderer, in which case the gear alone is worth more to them. Think of it this way....if you have a box with 6 rare, 17 uncommon, and 52 common tunes, are you really going to pony up much for a box that only has one more gear? I doubt it. However, that person might pay 5-10 million for that gear alone since they aren't going to want one almost done box (theirs) as well as a full box (yours). JMO. However, if you can get more for it, by all means do it. My point was simply that the number of COMPLETE boxes has probably increased by a factor of ten since the new quest. All the old rare gears used to sell for a fortune if you could find them. Now Valoria ships and Strike commander can be found as low as 25k. The ONLY gear that is worth much to anyone now is the Wanderer, and the last one I saw sold at auction within the last couple months went of 8 million, so your full box is not, in my opinion, worth much more than five (maybe 10), to the right buyer.