We have a large carport on the side of our house that we use as an outdoor dining space. We want to semi-enclose and insect-proof the space. We've decided how to finish the two end walls, but need suggestions for the side wall, which currently has two large concrete posts at each end and one in the centre, with 2 x 3.07m s,paces between.

Because of the land slope and potential for water to wash over the floor during heavy rain, we've decided to run two courses of concrete blocks along the base, which will leave openings approx. 1.9m high x 3.07m wide. We intend to insect screen these openings, but would like a clear opening or removable blind or screen of some kind as well, so we can have plenty of breeze in hot weather but have the space closed off, but still admitting light and the lovely view, in cooler weather. We prefer not to just use conventional windows. Many years ago, I saw removable 'windows' made from some kind of clear acrylic or PVC material. They just clipped in and out. I can't locate anything like that now, and I'm wondering what might be available that would serve a similar purpose - either rolling up or folding or sliding back?

Any ideas?