...is largely a hopeless prospect in this country (let alone the rising appetite for it world-wide, especially in China) for the foreseeable future, but: the Monterey Bay Aquarium's sustainable sushi guide
is a win.
A translation to both Japanese language and Japanese market availability would be a plus...
FWIW, a sushi bar here is actually a reasonable place to take a non-squeamish vegan. At a good place, there are a number of pure vegetable rolls. Not clear how much goodwill you earn with the sushi chef that way, but it's a much better menu bet than a tonkatsu (deep-fried pork) restaurant.
I can't promise perfection, but I can promise to do my best to follow the guide.
Now, how to popularize the ideas here?