Where can I buy Puerto Rican flowers in the United States?

I am trying to find a place to purchase a specific flower native to Puerto Rico called "flor de maga." It is also (in some regions) called the amapola or simply Puero Rican hibiscus in English. Anyway it doesn't seem to be a common flower here in the States and I am having a hard time finding a place (at least online) that sells it. And if it is not available here is it possible to have it shipped from Puerto Rico?