I have two singer machines and my neighbor also has an older singer. I went to Joann's and bought a walking foot for about 25.00. We had found them on ebay and also at the local machine repair shop, but Joann's was the cheapest. You get them from Amazon.com as well. We have been lucky so far and have been able to share most of out feet and other sewing gear.
I am enclosing a picture so that you can see what we use on our machine.
Also, from what I understand, this is sometimes considered a specialty type of foot so most machines do not come with one.
Singer Walking Foot
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