This is a double jackpot in a pattern envelope: "Scraps from the Past" and a clipping that was "In Search of Style". :D
The Clipping: Found in the pattern was this 1963 clipping for (remarkably) another pattern! The mail order pattern illustrates a lovely full-skirted dress with a snug bodice, short French sleeves, drop-waist points, and a portrait collar.
The Pattern: Simplicity 2413
The Simplicity pattern is very close to the mail order pattern and a wonderful match. It has a snug bodice with extended points, drop waist, full skirt (in this case with soft box pleats), portrait collar (in this case with a notch in front and a pert fixed bow accent), and short French sleeves.
The Scrap: Based on the beautiful blue color of this scrap that was tucked in the envelope, I would venture to say that the sewer was inspired by the color of the illustration on the pattern. The fabric is a soft, winter-weight interlock jersey in a vivid blue color. It's easy to picture!