I know there was an incandescent light version of the WST, but was there an incandescent version of the 7002?
As far as I know, no. I do know that Wheelock specifically decided to use xenon flashtube strobes for their horn/strobe units as an incandescent light could burn out from the horn’s vibration. You can read about it in the 7002’s patent application.
Maybe that’s why the Simplex 4050-80s in the library at the school I went to for kindergarten didn’t work? (the 4051s did though, and the rest of the school had functional 4050-80s as well.)
BTW, it seems that Wheelock had pretty much pioneered the modern fire alarm horn/strobe back in 1978-1979!
The 4050-80’s probably didn’t work because the bulb burnt out. Remember, the 7002’s strobe was mounted right on the horn, so vibrations would effect it more. Plenty of old light plates still work today.