Wow, this is really a difficult question and I am not sure, if I can help you, because I am several thousands miles away. But I wonder, whether you have found an answer yet. And if so, how was the fish?
If you were not lucky so far, why dont you try Casey's Cajun Fried Fish nearby Oklahoma. As far as I as know, it is not that expensive and you can easily dine there in casual clothes. Or, if dont mind to ride a few hours, I think, New Orleans Finest Fish Restaurant has some good offers too. But I am not sure, whether they really know the Japanese style of preparing fresh fish... ;-)