Welcome to Quilting Board. I'm going to guess you are not referring to the edge-stitcher attachment as seen on this page of the 201 manual
https://www.manualslib.com/manual/46...page=28#manual There is more about the edge-stitcher on the page before and after the one I linked to, but that page has the best image. I think the general purpose foot that came with machine the right toe is narrower than 1/4 inch. I did find this one that that the right toe is narrow, but says for 1/4 inch.
https://www.amazon.com/HONEYSEW-STIT...DW/ref=sr_1_24
Singer did make a gauge presser foot with different guides, but is a bit pricy unless you find it with a machine and the seller doesn't know about it.
https://singer-featherweight.com/pro...ntage-original
There is another image of one in use
https://d28lcup14p4e72.cloudfront.ne...tching%202.jpg
I'm thinking that a narrow hemmer could be used for narrow topstitching by guiding the seam along the left edge of the right toe.
https://www.singersewinginfo.co.uk/simanco/35857