@scothurwitz
Scot, I have a number of cartridges I used before the 9GSS. Benz LPS, EMT JSD 75, etc. You can see most on my system page. Just click on jperry at the top of the post.
Ikeda sells a SUT so I would assume that is preferred over an active step up. I use the internal SUT in my Luxman CL-38Uc.
If you are in Phoenix, AZ let me know
Good Luck with your search.
Jim Perry