There is a Gulf access from the campground. Sail right to park's boat ramp and out (left) in the channel to the Gulf.

I have used campground prior to Watertribe Everglades Challenge many times.(it's informal stage area for racers). There are a few sites with direct (almost) access to water. Yes, there are some king of obstacles normally, preventing from driving a trailer from the site to water edge. I have managed to squeeze my boats around. Instead of beach wheels I use inflatable rollers, which have a double duty as flotation bags. They are cheaper, take less space and more practical for “beach cruising”. They work great then I need to move a boat for a short distance.
http://www.praktek.com/
has them, look for beach rollers in catalog page.