I'm not exactly sure what you are looking for, but have you considered calling some local nurseries/garden centers to see if they have any? I don't know why you feel like you need to buy something like this online.

Not sure I'd consider lavender a good choice for south Florida.......I can't imagine the high humidity would be conducive to good growth or long term viability. This is a xeric plant that likes it hot (OK with that) and dry (not so good). Otherwise, I agree with goblugal - if it does well in your location, should be carried by local suppliers.