Started out at $9.99 but didn't stay there long. I'd love to have one of these some day just for a display.

http://cgi.ebay.com/RCA-1846-Iconoscope-Tube-1940s-TV-Camera-Tube-Exc-/140418387911

(no affiliation)

I definitely saw that as I am starting an old camera tube collection, as usual something of this vintage goes for prices beyond my current budget. Will have to try my luck buy me some scratchy lotto cards lol. At least the image orthicon tubes that appear on Ebay go for prices within my budget, managed to win a couple of IO tubes.