I’ve attached a few more photos to help you unravel the mystery. In the first photo you can see one spring that is properly functioning (left side) and then one that is missing the spring but the rivet/post that retains the spring is still present.
If you look at your post (#13- the 3rd & 4th pictures) and compare it to the first two pictures in this post you can start to get an idea. The rivet/post in the first picture, right side, holds in the spring and has a washer that acts as a retainer for the spring – now missing.
At this point, I believe the rivet/post is either spot welded in or pressed into the inner guide – (see pictures with the blue tape). The inner guide runs the entire length of the vertical channels. From your pictures post (#13- the 3rd & 4th pictures), your inner guide is either missing entirely or is so badly warped/ rusted as to make it worthless.
I’ve ordered springs from McMaster-Carr today.
Channel is constructed of 1/16” thick steel.
Height: 55/64”
Width: 57/64”
Inner width: 51/64”
Height of inner guide is 95/128”
Feel free to send me a DM with your email address if you need additional pictures.
Matt