Ooh, that sounds yummy. I wish I had a good recipe.
Everything I have read and been told by the pediatrician says that it is totally safe to eat things like sushi and ceviche while nursing. The things that were harmful while you were pregnant passed through the placenta. They won't pass through your breastmilk the same way. If you get food poisoning from something, it won't pass to the baby through milk, just make you sick. The only time you might need to avoid any food is if you notice your baby has a sensitivity to it, like spicy foods, things that make you gassy, caffeine, dairy, etc. But only after you see that it is bothering baby. I didn't eliminate anything from my diet while nursing, except most caffeine, and I was careful with alcohol. And I think technically the ceviche isn't considered raw anymore since the citric acid actually "cooks" it (similar to some meats being smoked). But sushi definitely is raw and that is ok to eat.
Now I'm gonna have to go figure out how to make it. I know I won't find any here in restaurants, and I love it!