Handle printed from PET-G at 15% fill , very hard and completely sufficient. More will just be a waste of material and time.
Holes in the bracket 15mm dostowanowane for aluminum tubes fi15mm available in any construction store.
In order to plug the holes and prevent the tubes from moving I added a PLA dowel with a slightly larger diameter then I heated the ends of the tube with a blowtorch and pressed the dowels into the tubes so they are really stiff and hold well.
The author marked this model as their own original creation.