I copied that into google translate and it SAYS it's english...but I'm not quite getting it.
you want to build a marquee box? or are you looking to find something clear to cover the front? Why concerned about weight? Thickness maybe?? the thread you linked contains a single picture of a standard machine which would require a single piece of plexiglas to cover the marquee.
Most hardware stores that carry full sheets of plexiglas often have "off cuts" or broken pieces for cheap. Sometimes you must ask if they have anything like that. You could likely find a piece that would cover that marquee 3 times over for $20
