So at one particular time, Emus were supposed to be this hot commodity and replace chickens because you were able to get more meat from them.
Unfortunately, things didn't turn out as some people expected and the market for Emus has severely dropped.
While I do not know exactly how much an Emu egg goes for these days and whether you are looking for one that is unhatched or just a Emu egg shell, you should be able to find either for a fairly cheap price.