in a diferent site someone sugested it maybe a 5 im going to get better pictures i think I do see some other things that suggest that it may be die chhip
i think that the die was damaged by a piece of foreign material caught between it and a planchet causing an impression on the die, then transferred to your merc. just happened at an interesting spot.
^ if thats how it happened, yes. there is a semi-popular seated liberty half that is collected because of the same thing. it looks like she is holding a cigar.
I would have someone qualified to look at it physically. Just to be sure. Pics are not the said stone
It wouldn't be a variety in my opinion because the anomaly wouldn't be attributable to the die manufacturing (making) process. It would be the result of damage to the die during the coin manufacturing (striking) process.
its just a matter of personal opinion. in my mind, a true error coin is a one-off. when an error is repeated over and over, i believe it becomes a variety. i would point to the "rust state" quarter as a reference. that being said, it doesnt mean it is a COLLECTIBLE variety.
The font doesn't seem to match any "7" I've seen in the Mercury series. It's clearly not a "squeeze job". I was thinking it might be a "dropped letter" from the "L" in PLURIBUS (as you suggest), but the angle doesn't seem right. Also, I can't tell for sure from the pictures if the "7" is raised or incused. Can you tell?
You are correct - it is a matter of personal opinion. I am not familar with the "rust state" quarter so I cannot comment on it. Any damage inflicted upon a die will repeat over and over on the coins it strikes. Even mechanical/machine doubling repeats over and over until the coin press is stopped and whatever is causing the die chatter is fixed.
I'm not experienced with overlays, but photoshop usually gets the job done. In my experience, I would put a picture on photoshop, then add the other picture I want to do the overlay with, and then just make that layer transparent...