Are these 340 manifolds worth anything?

Asking what an item is worth is almost impossible to answer. I always say "it is worth what someone is willing to pay for it". Case in point, I listed a '68 hemi intake on Ebay with a $475 reserve...it was bid to $425. I waited two weeks and relisted it and it sold for $675. So what is it worth ? 425, 475, 675,
see what I mean.

I agree, things change too quickly. I bought something off of Ebay last week and thought I got a good price, next day same thing was listed and it sold for $125 cheaper.