YuryShpilev: Well. Though it is time-consuming, there is a way like this.

Click "Raintings" on the main page and then click "Japanese Chess" to go to
the Rating players list. And then click "show all started games" on that page.
Then you can see 9 page of the list of started games with players' nicknames.
Compare them with the provisional BKR players. The difference should be the
unrated players that you would like to know.