With Damian TS826's permission (as it was he who discovered the calculator the keypad came from) I'd thought I'd post some images of the calculator I managed to recently find.
Firstly here it is in it's original condition. Closed:
...and open:
Here's the first incision I made to get to the innards. I'm lifting the back of it in this shot:
And with it flipped over. The keypad is the part with the circuit-board type layout on the back:
Then I removed the keypad from the calculator:
There's some debate as to whether the black edges are present on the original prop. They're where the PVC cover of the calculator are heat-welded to the plastic of the keypad.
This explains why there's not a line at the top because of course I had to cut that off with the rest of the keypad:
Here's a small animation (thanks Mike!) of the keypad I have superimposed over an image of an original Motion Tracker:
Apart from some distortion that's probably from the lens of the camera that took the original image I'd say it looks spot on.
There's a bit of an optical illusion going on where as the black line fades in it looks bigger, but if you keep your eye on the white borders of the keys and where the keypad finishes on the original photo you'll see the edges actually match up as far as I can tell.
In the spirit of sharing and all that here's a 300dpi image of a scan of the keypad. For reference the keypad itself should measure 48x43mm
For those of you who like a cleaner (but less accurate) look Mike Rush very kindly re-drew the scan in Illustrator. Here's a link to a download of his file:
http://www.triotech.demon.co.uk/keypad/MT.tif
I can't show the keypad on my MT as that's in storage but I'll try to grab it soon and will post here when I do.
Hope this helps!
Harry