I am seeing signs of a struck through, but that is def a broke hub on the D. Is there value in these type pieces?
The lack of detail is the result of a poor strike - not a strike-through. Poor strikes are typical of this odd denom. And what in the world is a "broke d hub"?
The absence of the top of the 'D' isn't the result of a die break. Think - when a die break occurs, and a coin is subsequently struck, wouldn't the metal (in this case CuNi) flow into the crevices of the break, creating a "cud" on the coin? My theory for your coin is that the dies were poorly prepared. When the working die was created, the secondary devices weren't struck from the master die with sufficient pressure to fully transfer the design.
Well, sort of. Die breaks are usually only referred to as "cuds" when they connect to the coin's rim. Die breaks can occur pretty much anywhere on the die face, so if one occurs near (lets just say) a coin's primary device (distant from the rim), it would simply be referred to as a "die break".
frankstony had it correct in the first place. The top of the D is open because the HUB is broken. On the hub the D is raised and the top of the D chipped off. When the hub then made the die, the top of the D was not there so there was no void in the created in the die and coins struck from that die have the top of the D open. The top of the D seems to break fairly often. It can be found on two cent pieces, three cent pieces, shield nickels, seated half dimes and probably on others as well. It does not command a premium.
how can I find out how many if any of these no D 65s are out there? Is there like a Snow of 3 cent pieces?
Well Allan Gifford in his book on Three cent pieces lists 32 varieties for 1865 and 14 or them have the open D. So I would start with an initial estimate that probably close to half of the 1865 three cent pieces have an open D.