Tom, if you are aware of the law, as it appears you are, then you must know how fruitless copyright suits end up being because they are essentially impossible to prove.
The major thing that must be proven is that the product being offered is A) directly affecting the ability of the original item to be profitable (Whether through sales or intrinsic value); and B) This is the tricky one that it actually infringes on YOUR work.
Even if someone is to charge for a replica, they can claim they are charging for parts and labor, not the artwork, as it is incidental to the process as a whole. It's a case of gestalt. Furthermore, point A is easily disproven through millennia of case history. Does having prints, or replicas of the Mona Lisa reduce its value? No, it increases the awareness for the art and thus increases its value by increasing the audience. The same can be true of the Evil Dead films. While popular for nerds such as ourselves, the percentage of people who are aware of its existence (And the necronomicon by extension) is tiny. People creating props and replicas can actually increase the value of the original by making it the sole original in a sea of replicas.
When it comes down to it, yes you have a right to defend your intellectual property, but the question becomes: to what end? Are you increasing your work's value by posting here and accusing people of theft? I'd argue for the opposite. So if I had one piece of advice it would be: relax and enjoy the fact that you created something so cool that people can't help but want one.
Copyright infringement is not a battle you can win. Even if there is a suit and you are the victor, court costs alone would far outweigh any financial settlement. So let's all just do what we all come here to do, enjoy and replicate props from our favorite films.
-Nick
PS: As a forum is a written medium, any defamation here would be "libel" not slander.