Is Casu Marzu illegal in the United States?
You ain't going to get anything like that into the states legally - not with the chance of livestock still being viable in there. It doesn't need pasteurising,it needs paralyzing before it will get past US customs.

You might get some included as a component of a cooked product, if the paperwork assures customs it doesn't actually cause death.

If you want a strong tasting cheese, try looking for Vieux Lille.