I agree with Bryan on the prices: $25-$maybe a couple hundred max, depending on the cabinet style and the condition... If I were in the market for one, I probably wouldn't brag it was a great deal unless I got it for $40 or less. I think many of the sky-high eBay prices are being paid by new collectors, and others who "gotta get a round set now". The most I ever paid for any post-1960 round tube color set was probably the $85 I just paid for this Zenith a couple weeks ago, which is as-new condition except for the busted CRT. A CTC-15 is a good set, but not really collectable yet. Once a year or so, I still see them lying in the alleys of Los Angeles. I used to drive right by, but now I stop and check them out
They aren't very rare, and if you miss this one you WILL find another in the future... Many TV shops still have one or two buried in the back.
Charles