Mechanical Doubling IMHO (Did you forget there is a Error Coins forum) (Just making a suggestion mods)
Keep in mind some of the Fonts used over the years on various denominations had different characteristics that if you look for a serif/notch of one font that is common in a given year may not be for another. There are 11 DDOs for your date/mm, but I don't see a match. With your coin in hand, have a look here: https://www2.briansvarietycoins.com/listings/cat/16 Basically, the splits/notches you are looking for look like this (this is for DDO-001 at Brian's site): I would recommend checking out Brian's site as there is a load of information and things to checkout. Good luck on the hunt!!
It already kinda is Errors, Varieties, and What Is This? But what’s in a name? They post just about anywhere anyway.
They can be pretty crazy. Unfortunately, it doesn't look like Brian has any DDOs/DDRs for the date/mm. His inventory are always MS coins (from what I recall) so those silver war nickels really sparkle.
Not yet but I can tell it's on the horizon. The comments today "I can't do this all by myself" tell me so. I just smiled and said, "Just have your brother help you".