Banister Pole Insert

So in my house we have a spiral staircase. The Banister are metal poles connected to main banister rail via a large plastic hinge.
Due to my children swinging down the rails like monkeys some of lower plastic connectors are broken.
There are no identifying markings, logos or serial anywhere on the structure so I do not have a clue to the make / model / manufacture of my staircase and after months of searching could not locate the replacement part.

So in the end I decided to have at go a making my own. We purchased the cheapest 3d printer (£100) available and downloaded blender.

This was the result.

USE AT YOUR OWN RISK.

Broken plastic is easier to fix than broken legs so if you using this please destructively test your prints so that you are confident of its strength.
If worried the part may fail it probably will.

Please see notes below.

This is the first thing Ive ever made and I suspect I could be improved upon so Ive included the original blender file