A visit to a medical clinic to get your regular prescription refilled ought not cost you $100's out of pocket, I'd of thought.
There appear to be many (dozens?) of nurse practitioners working in your own area in or near Leesburg, FL (why try to get a renewal online?).
You're going to have to visit a doctor in order to get a prescription for your levo as very few doctors will write a script without seeing you, unless you are an established patient. You can, however, go to a walk-in clinic, where you will be charged according to your income, which is often very little.
It's important to note, that if you haven't had thyroid blood work in a while, that may also be required, as well, but the doctor you see may give you a script to tide you over until that can be done.
Prescriptions are written online unless you are already established with a doctor and they write the prescription via their patient portal.