Help Needed: Can you identify this novel with a body-parts-for-sale plot line?

Help Needed: Can you identify this novel with a body-parts-for-sale plot line?

Mark Tushnet emailed me with a question I couldn't answer, and I'm hoping one of you kind readers might be able to help:

I'm trying to locate a novel I read, published in the last decade but not one of those on your list in that post, with the following plot line (it's a subordinate plot line to the main story): A person needing money sold a small body part, and prospered, but also found the sale altruistically satisfying. So, part by part, he sold off major body parts, to the point where he was reduced to a torso and head carried around by his close friend. In the end, a recipient of one of the body parts invents a technique for perfectly replacing lost body parts, so the donor is at the book's end restored to a full complement of body parts, mostly "artificial." (I use the story in teaching about legal regulation of risk -- students tend to think that there's something wrong about selling some body parts, although they disagree about where to draw the line, but don't have any objection to "selling" the risk to those same body parts at ordinary, risky jobs.)

The main story line probably had something to do with the "amputee's" friend, but he can't remember any other details. It's not any of the novels mentioned in this post.

If you think you can identify the story, you can email Mark at
mtushne (at) law (dot) harvard (dot) edu
or leave a comment below.