While I'm not in FL, I feel your pain. Without contacting every holster maker I've dealt with to get info on all their respective finishing processes, I know that
Desibens Gunleather uses a "Angelus acrylic finisher that is a form of a plastic which is used as a water barrier" that should in theory help repel sweat.
He sent me a holster to review which I did here:
The Rise of Rhome, A Review of the DGL #2 IWB