It turned out to be the drive and amazingly *only* the drive, and the backup turned out to be easier (though it took several tries) than expected. So I'm getting a new drive, and the total cost for the backup plus installation of a new drive (and new cable (plus tax) will come to just $367.

Yes, I'm pretty blown away and happy and relieved, and so on. They didn't call yesterday or today, so I'm guessing it'll be Monday before I get it back. But that's okay since I'm at a Zen retreat this weekend and won't be spending much time online anyway.