the plywood's fine, especially for something that short. go to the hardware get a can of super glossy spray polly and spray that shit good. use the whole can. then wax it.
Plexiglass works well although it is kinda expensive like 20-30 coin for like 32" by 43" piece. But if you do buy it make the measurements out and have the people at Home Depot or Lowes or wherever cut it for you. Because its hard and it will break if your not careful. Then use some lumber lock or liquid nails to apply it to the box. Unless you can get skrews that are below the plexi glass so you don't catch an edge. Also if you use skrews don't tighten them aton it will break. But if you use the adhesive put something heavy on top to keep it down and let it dry for like 3 hours
