measured from an actual item, drawn with only 4 basic components
since all of the rectangular units are instances of one component definition, it will be easiest to reconfigure it to suit your space using the move and scale tools in edit mode for the overall component but outside of edit mode for the individual elements.
to do the rectangular element, go into edit mode for the overall component and use move with inferences to position the vertical elements. then use scale on the horizontal elements (making sure that you're only scaling them on one axis at a time) to change their length or depth
to do the rods, move them with their ends to the position you want, then move the open or closed end separately to the width you want, then use scale on the rod (again making sure to have the center red box or grip selected) to change the length of the rod