What I have listed in the first post of this thread is what I bought and where I bought it.
As for the clearance....Where you testing with all Subaru parts? I'm not sure which bolt you're referring to as the shoulder bolt. It's possible it'd work, but with the setup I have on there, I didn't want to take any chances. Plus it's been a while since I've done this, and don't remember all the details.
I think 3/4" overall length may be too long. From looking at this picture:
two 3/4" flanged bushings wouldn't probably fit in that center joint. I'm sure you could sand some of the material down.....I'm not sure if Delrin or Teflon would provide any better properties when compared to nylon. You don't want the material to be too soft, because then it would wear out.....and I'm not sure how either of those two materials compare to nylon.