Well, if you are willing to up the price by 50%, you could cruise on over to Seattle (I'm assuming you are in Idaho) and get a custom tandem built for around $4500-5000, with S&S couplers, at R+E Cycles. After many years of touring on a pair of half-bikes, my spouse and I got our first tandem in '88. It was simply a game-changer. We could travel farther, faster, equalize fatigue (and thus crankiness), chat more and generally enjoy the ride much more than we ever did on singles. Also, the people we meet just seem to treat us better when we are on our tandem. I guess it is just unusual enough to be an ice-breaker (we do female captain, large male stoker).

Good luck finding bikes that work well for you.