there had to have been replacements available thru the early to mid 70's I would think. I know you could still get a 21FJP22 in 1981 but they were getting scarce. I would agree that people did tend to repair more back then, BUT technology changed so fast back then as well that they would have been pitching CT-100's left and right. There would have been a world of differance in a 1954 tv compared to a new 1967 model. I sold Zeniths in the late 70's early 80's and we had customers opting to buy a new set rather then have their 10 year old models repaired. These would have been the CTC-38's which would have been 10 years old at that time. Also.... I remember from "housecall" days that if the lady of the house liked the cabinet, that set got repaired no matter what the cost!