Welcome to Permies, Mark!
Your list of amendments is admirable, but expensive. Would you be interested in stuff that is roughly equivalent, but free?
How about calling you
local power company and seeing if they are doing any line maintenance tree trimming in your neighborhood, and can you get a load of chips? Actually, for 5000 square feet, you might need two or three dump truck loads.
Is there a barbecue joint there in Ocala? If so, they throw out lots and lots of bones every day they are open. Bones are all you need to take care of any phosphorus deficiency.
Seaweed? Like you, I'm a 2 hour drive to the coast where I could go and collect some, but I haven't done that.
Wood chips and
chicken manure and
biochar and drywall (for the calcium) are my main soil amendments.
When you say you want to add clay, is that because you have especially sandy soil in your garden?
As far as getting some biochar for your garden, follow the advice in this
video. I believe he is somewhere in central FL, like you.