If you were outside of AT&T, it was distributed via AT&T Summit's 'toolchest' thingy (and were as a single license to join it and but separate fees for each tool - if you wanted sub-license there was a secondary process which I forget the details -- I remember used it so we could make ksh, mk and ditroff standard on the MASSCOMP and later Stellar boxes).
My memory is that the toolchest was created before SVR4, I want to say SVR2 (maybe as late as SVR3) timeframe. Its origin is it was a way to get some of the tools that came from different teams around the labs out without having to including them in a full release. Earlier, Brian's ditroff and Dennis's compiler were licensed (together) but using the original licensing/distribution scheme. As tools like ksh and mk came on the scene, Otis Wilson asked a number of us customers what to do. The toolchest was born from that discussion. It was cool in the after you ordered, you go a uucp address to 'pull' the bits for your site from the toolchest. No tapes were written - which is why I think find things now may be hard.
That said, I've not found a repository of the toolchest stuff as I'm not so sure ATT really released all of it in the sense of the basic system itself. For instance, the support for the JERQ (including the games) were all in the toolchest and last spring a few of us were looking for the GBACA sources. I'm not sure if they were found.
Basically, you need to find someone that had had a toolchest license for that specific tool and still has the bits somewhere.
Clem