Thanks RAdiokid! That sure makes sense. Here's a photo of the plate that Takashi's mom gave us.
http://farm4.static.flickr.com/3109/...2d4dc3.jpg?v=0
And the one that we picked up today:
http://farm4.static.flickr.com/3077/...9b7096.jpg?v=0
There are more photos of it and the little booklets that came with them on my
Flickr: simplysilly's Photostreamflickr site.