Unless you buy a "youth" rifle, I believe you will be disappointed with any 243's weight when compared to the same model in 308. When sit in a ladder or climbing stand, my rifle sits across my lap. If in a box stand, the rifle may be on my lap or propped in a corner. So I do not get fatigued from "holding" my rifles when sitting in a deer stand.
Now if you just want a 243, that is another matter.