John, and others, my first treadle is similar to yours. It's a VS National/ New Home and remains my favorite. I've rescued at least three! They sew wonderful stitches and are very easy to treadle all day long.
Since you are already familiar with Singers and like them, I'd steer away from the head. It is not difficult to find a head and treadle set that will be compatible. Follow your gut and possibly consider finding a Singer treadle without a head. Place one of your machines in it, disconnect the motor belt, and use the treadle!
Annette