Just to follow up and close out the story of this sword, if anyone's interested: I received the sword on Friday, and the blade is just lovely. There are a few more ware than I noticed in the photos. I'm not sure if this was because of, shall we say, artful use of the digital camera and photoshop, or if I just didn't pay close enough attention. But it's nothing beyond the pale; like I said, it's lovely.
The tsuka (including the ito and same) is in better condition than I expected; I may keep it for a while rather than have a new one built -- still not sure.
It was shipped pretty poorly -- just bubble-wrap inside a cardboard box. Cheapo $300 Chinese swords ship in halfway-decent wooden boxes, and even $40 beaters ship with form-fitting hard foam inside the cardboard; maybe expecting a nice wooden box was unrealistic, but I would hope that for $2k+, I would get something better than bubble-wrap... Nonetheless, it doesn't appear to have been damaged in shipping.
My only real disappointment was called by Taz575 -- the tsuba has a ridiculously sloppy fit. It's not just a little bit of play; it slides wildly all over the place with no resistance at all. The tsuba appears (to my untrained eye) to be legitimately old, but it seems equally clear that it wasn't original to this sword. Oh well; I'll find someone to add sekigane to fit it to the blade.
The saya also rattles a bit. The habaki and the koiguchi make a good firm fit, but the blade slaps inside a bit.
All in all, I'm pleased.
Again, thanks everyone for the advice and the intro to this community.
- Bryant