Its hammer time..
Quick and simple - a tool to use, nice weight and balance - getting there...
Straight handle, tapered on the sides.
Make a jig to hold the brass bar - drill 2 holes - coping saw out the waste then file ready for the handle - fit this slowly, plane a little tap it in etc.
Araldite and lump hammer on the wedge set this, excess left on as it expands slightly helping retain head.