I have seen a number of different Paulson metal insert chips. A few have no date. Most have 3 or 4 digit numbers which translate to a 1 or 2 digit month and a 2 digit year. If Paulson made this chip in January of 77 and for some reason decided to put a slash between the 1 and the 77, then made some more in November and date coded them 1177, I would find that quite odd. I would think if it was a slash, the angle would be more pronounced. Here's one of mine. Looks like two parallel lines to me.