Your agent should be willing to take care of this for you - that's their job. And cruise specialists who do this all the time will have the names of companies they use on a regular basis for groups.
And yes, there are several companies with large enough vehicles for your group, that's not a problem if you want to keep the whole group together.
Keep in mind that the Ft. Lauderdale airport is only about 3-1/2 miles from the cruise pier and taxis are only $12 each way (not per person) and taxis are readily available. So if you don't need to keep the group together, that's the quickest, easiest way to get the job done.