Nothing there - they used ALL the metal for contacts..the miserable cheapskates :-)
Usually, we'll put logos and copyrights on a die on top metal. Some entertaining examples (if you're a geek, anyway) here, starting 1/3 of the way down at "A Dog's Life" - sad that they have never heard of THUMBNAILS: http://micro.magnet.fsu.edu/creatures/
Back in the early 80's it was not unusual for GEC, Marconi, AT&T, and other telecom guys to make their own transistors, so all you'll find in that case is an internal part number that even the internal guys had a hard time finding specs for.
I'd say you spend some time on a dozen or so on a curve tracer, characterize them (which is what we do in the industry anyway), and call it a day. The silence on this query is deafening - I'd have thought one of the old timers woudl come forward on this one for you.
Now you need to spend a few thousand dollars building something for these supposedly FREE devices...