I had been looking for one of these for a long time. Finally got this gem at the Marin County Guitar Show in 2003.
The actual date on these is a bit sketchy. I used the pot to date this one. CTS pot dates at the 49th week of 1978. I figure the pedal was assembled at some point in 1979. This unit is the later "block logo" version.
I really use this pedal only for messing around playing old Van Halen stuff, and on my bass solos. I prefer this one to the reissue.