Replaced the water pump. Watched a video from AppliancePartsPros.com online, and had confidence we could do the work ourselves. Ordered the part online at AppliancePartsPros, and it arrived in 3 days (thanks!). Replacement went quickly and easily. Getting the door back on took a bit of finagling, but I would attribute that as much to our inexperience with dishwasher repair as anything.
The dishwasher is back running normally, we saved a bunch of money and learned a few things along the way. Over - very happy with APP!