Looks like it could be done by stepping it a few times. Might not be worth the effort or cost of DME. A stirplate would be very helpful but not essential.
Why not try it? If nothing else, buy some other yeast, brew a batch, and keep a liter or so of your wort (diluted to proper gravity, if need be). You can use this as a starter, and all you're out is the extra money for that extra 1 liter of wort.
I would be worried about all of the dead yeast in that packet smelling like death and giving my beer an off flavor no matter if I did a starter or not. There are probably some live cell in there, but what would be the use in using them if the dead ones come with?
My opinion is that it is too much work to brew a batch to take that chance. Others may disagree.
If you made a starter and pitched at high kraeusen, being careful to leave the layer at the bottom, you'd get relatively few dead yeast cells, assuming the yeast is viable enough to actually go in the first place. I'd give it a shot, if just to save money on the yeast.