All the stormtroopers are clones. The words Clone Wars is used in A New Hope. They are clones of Jango Fett same as the ones in Attack of the Clones. Yes I believe "Aren't you a little short for a Stormtrooper" does imply they are all identical. If the empire was simply recruting troops they would come in all different sizes. Even if they prefered larger size they would need alot of troops and there would be Stormtroopers Lukes size. Mark Hamil is not that short. There is no evidence they are not clones. They do all look the same proportions.