I was able to get a proper STL file from jan-jaap. Going to find a local guy to print some for me.
Will advise with my findings.
Meanwhile, shapeways.com has some compression caps available, but pass on those — they’re tiny — better for the Barbie’s First SGI Playset instead of a proper Octane.
I'm interested to see if anyone has some close-up hirez picts of the PCI card-cage Pressure pads to see if the one I have is messed up or not. The very end piece seems to have a plastic film across it- and that is connected to the metal plate that seems loose. Is that how they are supposed to be? I'll get a photo today and post.
Last I booted my Octane I seem to remember hinv not showing the cage itself either. I think I have heard other people say similar things. I will be doing an IRIX reinstall on that Octane soon though so I will poke it both from the PROM and from IRIX to confirm what it says.