I cleared the place out of all the J-Frame grips that were available in the entire show--namely, a single set of Pachmayr "Gripper" grips. Not at all what I wanted, but for $10, it's hard to go wrong, and I won't feel bad if I try to cut them down to the size I want and butcher it. A little bit grungy, but with a toothbrush and some soap and water, they'll clean up nice. I also found a package of CCI 38 Special shotshells for cheap, so I got them, too.
On the way home I stopped at the last gun store that I haven't checked yet, and they, too, have only Hogue Monogrips, which (I think) are ridiculously huge on the little revolver. [Added: Not that I think these Pachmayrs are any smaller.]
It's still weird to me that no one makes a J-frame boot grip with a covered backstrap.