The first one is still attached to the ship and on display in a specially-built box. Each of these screws are 18 feet in diameter, weigh a total of 32 tons and made of manganese bronze. They were so delicately balanced, however, that the slightest push in drydock would actually spin them.
Turns out that I really didn't have all that far to go for the next two propellers. This one is displayed near the entrance of Carnival Cruise Line's parking structure on the other end of the property. It used to be mounted in the Queen Mary Seaport Village but was moved a few years ago due to renovations.
One of them used to be on display in Los Angeles' Exhibition Park; I remember seeing it there on a field trip way back when. I've heard it said that it was the one at the Maritime Museum, but I have no way to confirm or deny this.
It also seems that there was a fifth propeller. This one was a spare, I understand, and melted down when the Queen Mary came to Long Beach to be used for things like commemorative coins, tie clips and the like.