possibly mid-late 60's or early 70's
Boxes - in the case of the purple-pink and red-yellow boxes, there were multiple shapes and sizes for different models.
1966 (not sure about '65) to maybe very early 70s: purple and pink printing. Outline of lamp on front.
1970s: red and yellow printing. Century on big box with Aristocrat & Coach on sides; back has four thumbnails (Carlisle at the dentist, Astro for the oil broker, kids groovin' to Mediterranean, Coach as grandma knits). Other sizes had the lamps pictured and an abbreviated three-thumbnail back.
1980s up until late 80s: red and blue printing. Century on front, Coach and Enchantress on one side, Aristocrat and Midnight on the other side. Four thumbnails on back, can't remember what offhand but they're different.
60s KaleidoLite and 70s Infinite Motion Lite are known in plain boxes.