Hi Ron,
That's the SE 'Sintereisen' version, allright.
'mit Eisenkern' on the right, 'Sintereisen' on the left.
The correct bullets for a 1912 Erfurt would be of the truncated cone design, nickle plated, brass case.
Shown is a 1917 package and two 1917 variations of the P08 9mm round (the switch from truncated cone to ogival was made around 1917). Both rounds shown date from 1917.
Note the canvas pull strap on the box, this is a feature of the earlier packages. In WW2 they switched to cardboard boxes with different lid. The older boxes also have metal reinforcements on the sides.