Well, to give a more definitive answer to the OP; You won't need much of what you have listed in your post. The requirements include all external components, so things like a charging handle needs to exist. Power cylinders and Hengstler would be assumed for an ANH variation, but I wouldn't argue with you if you replicated a specific model in ANH that was missing those.
Basically, if it looks good and has the things you would expect of it, you should be fine. Having all the other parts come from found real parts is overkill, but appreciated.