I think a head scarf would be too short; a neck scarf would be okay.
It will stretch much more than the maxiflex and the stretch band.
Just be sure to pull up gently and have something nearby to use for balancing so that you don't fall.
I have a MaxiFlex, which is fine, but I don't like the way it attaches to the foot. I'd rather use a band that I can let go of if I lose balance, so as to get both feet on the ground and prevent a fall. With the Maxiflex, your free leg isn't really free to move, even when you let go, because of the tension clip on the strap.
However, it does make it less likely for you to strain your shoulder or upper back, which can happen with the belt/strap/scarf.
The latter requires the shoulder/arm to pull that leg up and extends beyond your normal reach. I guess if you warm up properly, including the shoulders and upper body, you'll be okay.