This was made from scratch in OpenScad based on the simple design from @hugodarwood user.
The current default values are set for my Sony ILCE5100 standard lens with a 41mm internal diameter holder. You can adapt to any size by changing the values in Customizer App.
Printed in a Delta Black 3D printer from Natural Robotics
Natural Robotics Delta Black
There is no complexity in this object, print with settings as you wish.