A suitable replacement could be made from an iron coat hanger of the proper gauge.
Cut the hanger, square off the cut end with a file, maybe taper it a little, and lightly tap it into the Torx screw teeth.
The coat hanger was a much softer metal than the screw, so the Torx teeth would bite into the hanger wire, producing a wrench which was good enough for a few uses at least -- more if you were careful on replacement and future removal.
