Cruise.com via ShermansCruise offers a Carnival Cruise 5-Night Western Caribbean Cruise for Two with prices starting at $618. (Scroll to the bottom of the landing page and click "Book Now" next to the January 20 sailing date.) That's the lowest price we could find for such a cruise in January by $30. This roundtrip cruise aboard the Carnival Paradise departs from Tampa, FL, on January 20. Book this travel deal by September 30.