Stanwal: This was the period of the great distortion race, when everyone wanted to add another zero to their distortion figures using massive amounts of feedback. Measured great, sound? not so much.I second Stan's comments. Personally, I would avoid most solid state equipment from the 1970's (and 1960's), especially the brands that were made in Japan.
If you really want to come close to duplicating that sound, and if you can't find an original in excellent condition, I would look at inexpensive mass market brands, and focus on models that have extremely low THD (total harmonic distortion) specifications.
Regards,
-- Al