You can get just about anything you want. Might get costly, though.
You'll want to talk to the folks at the lumberyards in your area to find
out what they can get for you.
I'd think there would be plenty of large PT timbers used in Florida in
marine applications. You might want to talk to the folks that build docks.
If you get your search terms correct, you'll find many sites like these:
Where you are may make a difference. Our Lowes stocks 8x8 and 6x8 as well
as the 6x6.
If you have a owes in your area, go to lowes.com and enter your local zip to
search your store from the comfort of your home.
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