The repaint sticker is what a painter should put on after a repaint. I have seen a number of these or similar on repainted frames. That said many painters don't put these on but rather put on the original stickers or their own logo/id. A factory repaint will often have the repaint tubing sticker but again not always. I would still say this is a mid to late 80s frame. I see nothing that really indicates that it is earlier other than the seat stay treatment and the pump peg and I can't see the seat stay treatment well enough to make a real call on that.