The pictures are not very good, but it looks like die deterioration which is apparent in the date that can, in some instances, look like doubling.
I bought a lot of unc rolls from a well known seller on ebay and the ad said unsearched and by golly some rolls appeared unsearched. My 1958 roll had 2 unc bie with die chips in the 5 and 9 plus I found several die chips in the 5 and/or 9. Yes they are common but I paid maybe 2-3 cents per cent. I still have some unopened bank rolls from the early 1970s to look at. It's late now but in the morning I will add images.
That's pretty sweet and lucky. I would never buy "unsearched rolls" off of ebay, but I'm glad you were lucky