Hi stanleychs1437,
While the choice of materials in your mattress is a personal preference … IMO it would be well worth looking into different types of foam mattresses (polyfoam or latex foam or memory foam) because there would certainly be some good quality choices available for a twin mattress in your budget range.
The better options or possibilities I’m aware of in the New York City area (subject to the guidelines here) are listed in post #2 here that will give you a good starting point for your local research and some of the better online options I’m aware of that are in lower budget ranges are listed at the end of post #4 here as well.
Phoenix