Some of the Kits can still be found over here in the Shops, but it looks like there haven't been any new batches being produced.
Most makers here release a batch once a year or every two years.
OTOH, more and more action figs and toys(Yellow Submarine, Max Factory, Kubrick, etc) of the designs are coming out so Nitto might be thinking it is more worthwhile to use the licence rather than produced their own kits.
From what I heard Kow does not have any plans on releasing new designs that previously were not available.