During the recent sorting of Jack's sweet cache of Japanese top videos it seems this one about a bit of turning and painting of the Sasebo koma was lost (or placed where I have missed it). The pile of blanks shows the marks of a drive center from initial turning between centers in what is likely a more conventional lathe for the western audience. The lathe and jamb chuck used for finish turning and painting seems more Japanese style.
I suspect the "mass produced" blanks of Sasebo tops shown were made in one of the two ways shown in this kendama fabrication shop (sorry no tops but perhaps the NSTR police will allow it to pass due to the recent kentoppa videos
). For smaller tops a single profiled cutter could be used as is done with the kendama ball. If the size gets too large for a single simultaneous cut, a copier or tracer lathe setup can be used to cut a profile with a small cutter where its mounting carriage (cross slide) is tracked along a pattern cut to the desired profile as is done with the peg/cup part of the kendama. Of other general fabrication interest, notice the fantastic shop made collet chucks and closers which allow the workers to remove and install work pieces without shutting off the lathe.
http://www.youtube.com/watch?v=fBLtetnlgwQA similar shop (perhaps the same?) and again kendama but I would be surprised if these shops did not also produce tops of one type or another, but maybe the kendama are the real volume money maker.
http://www.youtube.com/watch?v=e33YgRTQHrsand a mom and pop shop where both tops and kendama are made without the more advanced technology. A quick view under the lathe bench shows the foot controlled operation of the lathe, I assume to engage the overhead belt drive and to quickly break (stop) the rotation after disengaging.
http://www.youtube.com/watch?v=KQoj4WKYjbA