On Autozone homepage here is a link to hydroboost #71117
http://bit.ly/1vMQE8o
The code is stamped in on the rod at the flat part just before the "ring" on a oem rod.
You can put in any car or truck model on Autozone webpage along with a valid zip code and search parts that will fit or even compare between different years by adding a new vehicle search.
I have bought for my own 1982 K20 Suburban diesel with JD7 brakes, a replacement hydroboost with # 52-7248, and that rod that comes with it is 14.2mm big in the "ring", so it should fit over the pin/stud just about perfect. So the difference between #52-7248 for an -82 or newer and the #71117, I don't know. The #71117 is not supposed to fit my -82 with JD7 brakes according to Autozone webpages. Maybe a Difference between attachment points at the firewall maybe?