This link shows model numbers of DuMont color TVs from the early 70s.
http://www.usedprice.com/items/video...tv-television/
The earliest is 1970. Unfortunately, no pictures. I'm not clear on the difference between "console", "portable", "combination", and "tabletop" - ours had a handle on top so it would probably be "portable". It was not a wood console like the one in the pictures above, and was probably slightly more recent. (Is that one from the early-to-mid 60s?)