This item sold on May 5, 2012.
The plastic is flexible with no cracks or brittleness. The box is a little bent up because it has been in storage for years. It has a couple of tears in the cardboard and has been glued. I removed the darts to clean them (they were dusty) then gently put the box back together. You kind of have to open the box to get the darts out.
This set is probably from the 70's