I know there are companies that offer different types of windows for he RV doors.
What I did was cut some plexiglass to fit the screen door. This allows me to leave the main door open with the heat or AC on so I can get light and see outside. Did the same on our TT. Didn't realize how great it was until we bought the Georgetown. After one trip I did the screen door. One of the best mods I have done.
2012 Georgetown XL 350TS, Hellwig front/rear sway bars, Sumo Springs, Blue OX True Center steering damper
2013 Ford Explorer LTD toad, Roadmaster Stowmaster 5000, VIP><Tow Brake
Better to have a bad day of camping than a good day at work!