I have my MK-VIII LCAs available. I can get measurements of the pocket. I can pull down the spring isolators as well and get measurements of the inside hole as well as height for overall perch measurements.I went with Aluminum "pucks". Basically just 1.5" chunk of 3" wife aluminum bar. I plan to drill a hole in the center for the bolt, then find a washer the thickness of the arm that barely fits in the bottom hole to center the puck, them a wider washer below it to home everything together. I'll have $30 in the perches. I'd really like to just turn a small protrusion that fits that pocket on one side on the puck, but I don't know if anyone with a lathe.
But yeah, we need someone with a lathe, lol.