Got some great news that might help others. Looking at the add-on walking foots available, most of them are pretty much the same. This morning I went and bought the Singer "Even Feed Foot", part 2500271.06 from Michael's. At first it would not fit my Visetti's square-ish presser bar. A little filing with a small file took care of that. I filed down the back white plastic face that the arrows are pointing to, thereby simply widening the area that goes around the machine's presser bar, making it fit perfectly. Don't need to go fast. A little filing, check if it fits, etc... Now I have a walking foot for my vintage made-in-Japan machine.
