Mifune Don Restaurant is a smaller, less expensive version of Mifune, which is also in the same area.
I asked for the eel over rice with cold buckwheat soba noodles, one of several specials till 5pm for $9. At their discretion, if it's not busy, they'll offer the $9 specials after 5pm. It was pretty tasty.
Monday and Wednesday to Thursday 11am to 3pm and 5 to 8pm, Friday 11am to 3pm and 5 to 9pm, Saturday 11am to 9pm, and Sunday 11am to 8pm; closed Tuesday.