Morocco has sizable Jewish communities. Polygamy is also legal in South Africa (where even the President has multiple wives), which also has a very large number of frum Jews.
In any event, I wasn’t referring to what the local gentile countries we’re living in permits. You could have a halachic marriage without undergoing a secular marriage. In the United States of America tens of thousands of Mormon Fundamentalists and African Muslim immigrants have polygamous marriages from New York City through Utah, and have been doing so from over a century ago through today.
Obviously, all this is currently only applicable to non-Ashkenazim.