Wooooow! A thing of beauty and a joy for ever.

Would it be possible to get the cad files for the gerbers? I want to make a board like yours but instead of a lpt port, I'll have onboard esp8266?

does anybody have a recommendation where to find a matching connector?

Hey, I've gone one working too!

Have you thought about trying to stop those horizontal lines from displaying? I can't figure it out but I believe it's possible just based on the following pictures I found randomly:

http://sim.loa.su/pub/_hardware/MC6205/MC6205.jpg
http://sim.loa.su/pub/_hardware/MC6205/MC6205-cut-___.jpg

It's a slightly different model to mine, and I'm not confident enough to just start snipping resistors until it works haha.

PS: If anyone wants to control it with an Arduino, this library is fantastic:
https://github.com/holzachr/MS6205-arduino-library

I all depends on your model of the MS6205. But in my case cathodes control the vertical lines, anodes control the horizontal lines. Some cathodes aren't connected at all (1px lines to the left and right of letters), and also some anodes aren't connected (1px lines above and below letters), but others are permanently pulled up to 240V.

If you have all the docs that came with your MS6205 it should be easy enough to find the anodes that are permanently pulled up and to remove the pull-up resistors. I'm a bit disappointed they didn't connect all lines to the logic chips. :/
Ping me with a PM if you'd like some help.

Fantastic advice, thanks @Leszek Jakubowski 

I'll give it a go at some point yeah, it seems like there is a lot more variation of the layout of circuitry in these devices than I'd expect. 
The horizontal lines are beautiful in a way, so I'm worried of breaking it but we'll see!

https://www.michaelcook.tech/plasma-display-mc6205/

I've got one of these, though I plan to eventually directly drive the display instead of using the built in driver. Maybe turn it into the world's worst E-Reader.

I also have this screen. I made it work and everything is fine with me (I even wrote a program). I recommend applying 30A GND to the pin to drive the monitor out if it is junk.
If necessary, I can send my program code for arduino

Arduino code would be fantastic.  I've been having issues with the software side, mostly figuring out the control commands to send to the display.

Awesome find. Looking forward to seeing updates on this! 

just waiting for the parallel socket to arrive.  Once its here I can try displaying things. 

I've seen pictures of it being used in a money counter for banknotes. I'll post a picture if I can find it again

Any idea what this display was used in ?

On the device "BANKNOTA-1". cnc machine tools:
MAYAK-221, MAYAK-223, 2M43, KM43, 2S85, KM85. And one rare comp ... On Wikipedia it is written (Russian)
You can also look where they use IMG-1-03 is an indicator in the monitor