I have designed a drop-in replacement of the Arrma outcast drive shaft (ARA311065) I think it is a stronger design as it is not hollow and is cheap to make if you have a 3D printer.
I have tested it on multiple materials and layer heights. To get the details to buy me a coffee on Patreon.
I have tested it and it has lasted longer than the original you can print as many as you want!
The author hasn't provided the model origin yet.