I use standard SSV screens, whatever they are (Got a pack of 100 from ebay a few years ago and still have plenty left
)
I don't lodge my screen between the 2 joints, I always lodge it right at the bottom of a Joint.
It can be quite fiddly getting them in there I usually use 2 stirring tools, one from each side, so I can more easily manipulate the placement of the screen.
Basically, I have to bend the screen a bit to get it into the joint.
Once the screen is completely inside the GonG joint, maneuver the screen so that bend is now a dome facing "Up/out".
Eventually after some kajiggering it'll just sorta pop into place, and a little bit of pressure on that dome will flatten out the screen a bit more and make it stay in place.
All my screens inserted this way are super sturdy, and give me zero issues with stirring.