Funny you should mention VAS, as my Proteus is on its way back from them with a new diamond installed. Steve has done an A90 for me in the past, and so I sent him my Proteus and a ZYX 4D as the diamonds needed replacing.
Steve will not do this type of Ikeda cartridge either.
Ana Mighty has done them in the past, but apparently has discontinued that service.
The only other person I have heard work on them is a fellow named Dmitry. However it sounds like he is on sabbatical, and as of March of this year was not taking on any other work.
Perhaps I set it aside and use it for a few weeks a year until Dmitry takes on work again.