Good luck finding the rebuild kit.
This guy on PBB seems to have luck finding them.
"I used a kit I found on Amazon for my 86 box. Brand and part number are : EDELMANN 8846"
I use to get them at the dealer when I ran a steering box.
Remember there are two different style boxes
Here is a link to their web page and the have them for the early and late boxes;
http://www.plews-edelmann.com/power-steering/
