So.. in summary.. you went to a sale where it is customary to find people selling all manner of items ranging from cheap to expensive and fake to real - where you saw an item that you decided was of a quality and price that did not meet with your purchasing criteria - and so you did not buy it.
In response to your original query - it has been established that yes birds can be taxidermized and yes some peoples attempts at doing so can be anywhere from awesome to downright scary.
So .. I'm really curious.. what was your intended use for the items if you HAD purchased them? Especially since it appears you don't even "like" the items in question.
I'm suspicious that some friend of yours is about to be "out uglied" in and "ugliest gift" competition. Or that you really don't like the person you got for secret santa this year!?