Not a Hobie 16 specifically, but Bradenton Beach Boat Rentals on Anna Maria Island (Bradenton's barrier island) rents G-Cat 5.0s and 5.7s, PWCs, and kayaks.

The owner's name is Ralf Cole, and the number I find listed is 941-778-4969.

Also, Glen rents boats off Dunedin Causeway (which is a very popular catamaran launching point), though I don't have the number. He used to have a couple G-Cat 5.7s... but they were for sale last time I was there and he was renting plastic Windrider Trimarans