Organ does make Janome needles.
I use Janome brand (from a local dealer), Organ (bought through a co-op) and Schmetz.
I have used Klasse in a pinch, but am not quite as happy with them. I really cannot say what the difference is, but they just do not work quite as well.
I have a Janome 11000 and an old Kenmore made by Janome.