Hi flora,
I don’t keep track of what each retailer or manufacturer offers to any great degree because this can change constantly and would be impossible to keep track of or stay up to date (even most websites are not up to date) but the list of the better options I’m aware of in the Chapel hill area are in post #6 here. If you call these to see who offers an innerspring/latex hybrid and has it available on their floor to test you will quickly discover who has them. You could also ask them about a mattress that just uses an innerspring and natural fibers but these tend to be much more costly.
Of course you could also choose to look at other types of foam or fibers depending on what you mean by “more natural” or the “degree” of natural you are comfortable with because just about every type of material has more or less “natural” versions to some degree but most people who are looking for “more natural” would lean towards latex or natural fibers in their comfort layers.
One of our members Bay Bed and Mattress also makes a pocket coil/latex hybrid that is great quality and value and can be customized to each person’s preference and shipped anywhere in the country.
Phoenix