I spoke to a licensing exec at Walt Disney Studios and they said that a 'replica' is an artists version of a prop used in film. It doesnt become an infringement, otherwise people would be challenging knock off brands of everyday things we see at stores we go to. NOW, the fine line is if you say for example, 'an exact replica molded from the actual prop', and that raises a flag as most of the time props are the property of the studio producing or in often times, the actors. In the case of Harry Potter, almost all props go to the studio for exhibition.
Just thought I would help.
Just thought I would help.