That is what I did originally. That should be what tube-socket-7pin.fzpz a couple of posts above is. Then I changed up to tube-socket-7pin-1.fzpz based on this theory (your drawing with more lines 
):
What happened on the 9pin socket is that the 9.5 diameter is of the pins of the tube that plugs in. The socket (as we see from the blue and red lines going to the picture of the socket on the right) are on a bit further out, the diameter corresponding to the 2nd circle from the outside. If the 9.5mm is correct then tube-socket-7pin.fzpz should be correct. Luckily I kept the original instead of replacing it!
Peter