My original repository for this item is on Thangs: https://thangs.com/m1n1ster/Astro-Armrest-Bracket-39855?manualModelView=true
A friend had issues with sourcing a replacement bracket for the Astro armrest. This is a model designed to be much simpler and sturdier where the peg is inserted. The original print has been installed and works great.
The author marked this model as their own original creation.