You can buy fruit trees at a nursery. Try Green Gems on SR 561 in Clermont, just north of Hiawatha Park.
They sell fruit, you could ask them about trees.
You pick or buy, different types of oranges, then there is limes, lemons, tangerines and grapefruits but I don't believe they sell trees.
I've seen citrus fruit for sale there but but their trees.
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