Take a look at this auction, here is an excelent picture of old bricks with the windows and doors which fit in the slots: (URL) these items definitely LEGO? I know that the early bricks had slots in them, but I'm not sure if the windows were (...) (24 years ago, 25-Jul-00, to lugnet.general)
I have those bricks and It comes in green (2x4 and 4x4 L bricks). I agree with you, I don´t think the windows and doors are original Lego. Manuel (...) (24 years ago, 25-Jul-00, to lugnet.general)
