There are lots of TVs from that era still around. You must be looking in the wrong places. Older TVs (pre-1970 or so) are advertised in the Craigslist antiques, collectibles, and electronics categories because people feel they are worth something. Most newer sets are considered junk, and actually cost money in most places to dispose. You'll find them in the "free" category. Even all the local estate sale business here either offer them for free, or will even pay you to take them.
Here's a big bunch here in Wisconsin (Craigslist - Free category), just waiting for anyone to pick over...
http://madison.craigslist.org/zip/5501962914.html
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