'72 Dart/Demon arm rest question

I am only really familiar with the doors off of my '74 Duster. I swapped them for a set from a '72 Demon and am working on the interior panels at the moment.

My question is about the arm rests used in the '72 doors. Are there two pieces to them, a base pate and am arm rest?

I am working on tracking some down and I am only asking because the arm rest in my '74 doors were one piece.

Also, is there much of a demand on here for black '73/'74 Duster interior parts?