Set shown is either a A4533W non SC or AA6533W if SC.
The E-bay ad is a A4533W. They are 23" 1970 models that would
have been released normally Sept of 1969.
Chassis was hybrid, about 1/2 tubes. Included the first duramodule
for color demod.
1971 "B line" added 25" also 19" with the new 4 tube hybrid chassis.
1972 "C- line" had the first solid state chassis.
73 Zeno
LFOD !