1943-P Jefferson Nickel. Overdate Or Die Chip?

Looks like a 43/2 to me. But I am no expert.

I am sure someone will know for sure.

You might try to remove the crud around the date digits. A little soak in mineral oil might help loosen it. Be careful pushing the crud around on the fields. Sometimes grit gets into the crud and if you push it with a tooth pick it will scratch the surface. Experiment on a normal nickel to get the process down before trying it on this coin. You don't want to mess up a variety coin.
Here is an image of the real thing:

What concerns me is the lack of the horizontal line in side the lower part of the 3. But you might check for location of the mint mark on the reverse?

Here's the reverse.

What am I looking for on the mintmark?

It does look like a match. Then it might be from that die. Nice find.

I just noticed the tittle of the thread. The use of the word "Over-date" is not a correct term. Why? Over-dates are a 19th century thing. The date digits were hand punched and sometimes they reused a die from a previous year. But in the 20th century the make the dies differently. All the devices and date are on the hubs created that year. The dies had the mint marks added to them. So an over date is no longer possible. The 1942/1 dimes, the 1943/2 Nickels and not over-dates. The die was not altered with a punched in date. The die was hubbed twice with different year hubs. So this is not an over-date die, it is a doubled die. (I'm sure their are other examples, but just these two years jumped out at me) 1918/7 nickels is another one that came to mind.

Now it shows the flat line in the lower loop of the "3". That is the correct die for sure. Nice find.

No...as coop stated, modern hubs have all design elements on them already...the only thing punched on a die is the mm and that ended in 1990.