Ameraucana have muffs from hatch. If yours doesn't have them now, they won't get them.
Hatcheries label their easter eggers as 'AmerIcana' all the time, note the spelling. You have to look close at the description. All Ameraucana, from a breeder or otherwise, will always list what the color type of that breed is; i.e. wheaton, blue, black, buff etc. Anybody who sells them, without a standard color, and it doesn't follow breed standard; i.e. slate legs, muffs and beard, pea comb, standard color... They're selling EE.