When Kirk and Kyle are bringing in the dummy and laughing about where he picked it up you can see Kyle's real hand. His metal claw is there at first, then it shows his real hand. Actually, it's Kirk's real hand that we see, not Kyle's.
A cannonball would not weigh "a hundred pounds" as Taylor mentioned. An iron cannonball of that vintage would weigh 12 to 24 pounds, and could easily be carried by one person.
At the start of the episode, the baby in the pram Sookie is pushing when they are in line to see old man Twickham is clearly a doll.