Another carb ID

[Keith True]

I recently removed this carb from a local mans car.It was acting up,so I fixed the Zenith that had been riding in his trunk since the mid-60's.It has a cast iron top,with a pot metal bottom.It has a strange enrichener??? circuit on the back.That has a broken spring in it and the car either runs rich or too lean.The plunger in it is just jumping up and down without the spring.I have quite a few old Tillotsons,Allstates,Wizards,Marvels,Simmons and such,but I've never seen one of these.I would like to use it.When it was working right the car idled nice and had lots of moxie.