Griffin, The 11:55 am arrival is within the flight guidelines by the cruiselines, barely. If you have the opportunity to come in the day before, that is always the best option. If your schedule or other reasons prevent it, I'd still move your flight to an earlier arrival time if you can.
There are cruiseline transfers available, outside transfers, cabs and other options. Since Orlando Airport is 45 miles from the pier it would be a pricey cab ride. Also, the transfers are sold per person and with 7 people, that too would be a pretty big expense. I would think sharing a rental car that can be dropped off at a location near the pier and a courtesy shuttle from the drop off to the pier would be the route I'd look into. That way you can rent a van and share the expense rather than paying individually for all 7.