At the local recyclers, I got what is apparently called a roller shade. It's 48x78 inches, black on one side and gold on the other with perforations. Two more showed up later as well --$25 each.
showroom.apexshutters.com.au/wp-content/uploads/2020/05/roll-shades-01-300x199.jpg
I shall get some window screen extrusion and frame up individual screens for at least four windows. One on the South for solar and the one on the North for privacy.