I thought the Iwatsu facility in Japan stopped manufacturing products in 2009, after a tsunami damaged the property. At least up until a few years ago there were still quite a few Iwatsu TDM systems out there, a few were sizeable with different sites networked together. There's some with their proprietary VoIP phone that could be integrated with TDM systems. I know of a company in New England that has, or used to have a stock of various Iwatsu systems, phones and components.