Aged Scotch, How old is it?

My friend just sent me 2 bottles of scotch that her parents got for their wedding over 40 years ago. I have looked in the boxes and on the bottles, I can't find a date anywhere. It's two bottles of Dewar's "White Lable" Scotch Whiskey. There are boxes! I can't remember when Dewars was sold in boxes! They're both 750ml & 86.8 proof. One of them has the red and white "Bureau of ATF" stamp tape over the cap; there are the letters "N.Y. - I - 68" on the tape (maybe that's 1968? Probably not... they were married obout 42 years ago, and 1968 was 39 years ago). That one is in a flat textured & decorated box. The other one has no tape over the cap, but the seal isn't broken, and there's a label on the back of the bottle too (haven't seen that before either). That one is in a white decorated laminated box. They're both upc coded "88100 01115". How old are they? How long is Dewar's "White Label" aged before it's sold? I will furnish pictures of the bottles and boxes, if you contact me.