Spring Garden Avenue in the Yonge and Sheppard area, specifically just East of Yonge has a few sushi restaurants. Kiyomizu is the most east but also the most expensive... not by much.
That said, the quality can certainly warrant the price. I've only been there with larger groups but each time, we got some salmon teriyaki on the house which is always nice.
Atmosphere-wise, I do find the place the most comfortable when compared to the others.