I'm purchasing a house built in 1937. All the windows and fixtures are original.
A fair number of the windows have an integrated screen that pulls down from the top of the window. The tracks are attached to the window, and I believe there is a roller integrated in the frame. I'm not sure what they are called, but I've attached photos below. Not knowing what they are called makes finding information about them difficult.
Most of the screens are like the one in the picture, and pretty much toast, but the few that still have intact screens work well (or would with some grease/oil). What is this mechanism called? Can it be repaired? Can I add lubricant without breaking the frame?