Copying a prop is a simple task,most could easily do it without fuss.
Getting a proper center balance and good hard grain wood and airfoil is another matter.
Anyone in the Hobby should have some knowledge of this.People buying on line trying to save a buck or two,will end up with seconds and fakes.
That is how this world operates now.You want cheap crap,its there for you.
You want performance,do some research,and buy a tested item.