I do not know which cup came with the original kits. Which cup will work depends on your flywheel, both the configuration of the flywheel lugs, and the depth. One thing you can do is measure the required depth of your original recoil cup and compare that with the vendor. All of those guys currently selling those FM cups are stand up guys.
I went through three different cups before finally modifying one that would work. I also tried the OEM cup as well as a NOS replacement. Nope.
So you have to have the right height, which was around 2.5" and then the lug pattern, which for me was three lugs off of a points type H30. And finally the bottom of the cup has to be thin enough to use the Belleville washer and flywheel nut.
Part number 14-3 and 14-6 are what I have left over. 14-6 is too thick on the bottom, so you'd never be able to use the correct Belleville washer. 14-3 might work if enough is cut out of it to fit your flywheel. I THINK I ended up using 14-370 after highly modifying it.
I am sorry I don't have more info. I too scrubbed the internet looking for answers. And when it's all said and done, those pawls are real finicky about engaging 100% of the time. These kick starters are perfect for pretty little garage gems and trailer queens, which is exactly what I plan on using mine for. Dave the Rokon guy has some cool photos of these units in pieces, shattered. I'm sure they were a cool addition back in 1970 though for the mini biker who wanted just a bit more kool in in koolaide. I mean I take that engine out of it's hiding place in the cupboard all the time, and just gaze upon it's koolness. And then I will slowly turn the kick starter, and feel how it knows I am not serious, and does not engage.