Yesterday I was in Japantown buying some substitute ingredients for a Malaysian dish (anyone know where you can get Palm Sugar or Malaysian miso?), so I walked up the stairs next to Denny's. There's a bar up there, and sure enough a small Japanese sign for the restaurant Kappa.
A hostess in a kimono greeted me, though it was only 4pm so they weren't open yet. She said they didn't have any sushi as a tactic to get me to leave, but when I started speaking Japanese with her she was pleasant and gave me their card. She told me that yes indeedy, the Kappa owner used to own Tekka before selling it to the current Tekka guy. I just got a glance at the menu -- lots of cooked food. The menu is only in Japanese. Also, from the bottles I saw, they have one of the best sake assortments around.
I was scared to ask the price, since I've heard it can be very expensive. Anyone have any firsthand experience?