A quick look around Craigslist confirms your statement. Most tandems showing up used there are from a time before tall captain/short stoker really took hold. I don't think that is that much of a problem. I may be weird, but I would much rather buy a brand new tandem in the $1500+ price category than something from 20 (40!) years ago that people can still ask (and get) $1500 for.

I met the woman that is now my wife in 2005. She was/is blind and had had some tandem experience. I had never even given tandems a thought till that time. The Fuji Absolute, KHS Milano, and Raleigh Coupe all represented the new tandem design coming to the forefront with the mixte stoker section that would fit a much larger size range of stoker than previous designs. The KHS wasn't even a 1/10 of the bike then that it is now. I would have bought one! I think a team could do a LOT worse for $2K. That said, you couldn't touch a Santana or Co-Motion in those days for less than $5K (Cannondales started at $3K) and both those companies now have bikes that retail at the $2K+ price point! And all (except Cannondale) will accommodate a short stoker, though I wonder how short a stoker the KHS will fit. But... what does it mean anyway if the stoker doesn't actually have to stand over the top tube?

If you need to spend much less than $2K you really have no choice but to get a Trek T900 and convert it to drop bars. With the right tires it could do Ragbrai. I think it would be WAY easier to find used components needed to do the conversion on the cheap than it would be to find a used tandem up to doing Ragbrai that wouldn't cost a whole lot more used than a T900 costs brand new.

EDIT: I obviously did not see the previous post before writing..