There may be a lot to sort out.

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Fairgrounds Expo center
Tampa Convention center
Large hangars at Tampa Executive Airport and Fighter Town near I-4.....I-net search for Fighter Town/Polk County.
Lakeland -Linder Airport hangar was big enough for a huge Trump Rally
Orlando Convention center
Daytona Beach Convention Center
Lakeland (RP Funding) center
St Pete Convention center.....but they call it something different
Gulfport Casino.

Some places may be willing to rent a portion, or one or more rooms, instead of the whole building.
Example: Tampa Convention Center has several rooms/halls as does the Lakeland center.

Look for places where they have held big gun shows.
Or start searching for places for rent that mention the square feet which they have available.

Check with real estate agents that have knowledge of abandoned grocery stores
and other closed large building businesses.
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