Well, this is embarrassing. I've got a brand new SMD Lunar Duo, purchased this month, that I've seam sealed. I love the shelter, but my wife feels more comfortable in the Shangri-La 2. I can't return it as I've sealed it, but it has never been used--just set up on our deck to seam seal it.
This is a tricky one for me to price. Usually I try to list a compelling price for used gear. But since this is new, and seam sealing normally adds $30 to the tent, it's more difficult. I feel I did a great job on the seal, but I know I'm not Ron Moak, and it doesn't come with a return policy.
So I'm going to list it at $250 shipped. With the seam sealing, this would retail at $305, plus the cost of shipping, plus the cost of seam sealer. $250 is the cost of the Shangri-La 2 and nest I got, so at least I'll make a wash on the sale.
So, to reiterate: $250 for a new, seam-sealed SMD Lunar Duo, shipping included.