Went on the 1/26 sailing, and I can only speak about the bike rentals (because that's what we did). They were PLENTY of bicycles available, so I wouldn't be too concerned about that one. In fact, our ticket had a rental time of 9:30am, but we didn't go there until 10:30 to 11am and it was not at all a problem.
Also saw plenty of floats available too. I would think that if you fill out your excursion form and drop it into the shore excursion box when they put it out (day you disembark from Florida), you should be able to get everything you want.