I think it all depends on where you live, how many people in the area are into these bikes and help jack up the prices, and what you think it is worth to you. In comparison to jk333, we recently picked up a '72 CL 350 for $600 with original paint, a bunch of extra parts, running but needs cleaned up, tires and new cables. Our '69 CL350 cost $450 and needs cleaned up, new tires and cables. Tank is rusty inside but can be saved. All normal maintenance type of stuff on 40 yo bikes anyway.
In PA, I wonder how many people in your area are looking at these older bikes? It makes a difference. I am from PA originally and in my particular area of the state, you couldn't give an old bike away. Now, the interest is starting to show and so the prices are starting to climb. It's all relative to your particular situation and the timing.