Bwirth - National sold most of it's machines under other names, so the "official" manual is most often generic.
National also liked to use the same basic model number for the machine even though it may have had some updates over the years. I've got manuals from different years with the same model number, but a slightly different looking machine. Some of my older manuals are from a time when updating the drawings was not an easy thing to do, so they used the same ones unless the update changed what was shown in the graphic.
As to the bobbins, some winders need that notch, some do not. I have not seen a machine that needed it in the bobbin case, as in all of them, the bobbin needs to spin freely. Sometimes the holes are there to run the thread through to make it easier to start winding the bobbin.