I'm kind of surprised no one picked up on what I believe is the thread cutter/holder that is in the second picture below & to left of the quilting bar. I think it is Singer part number 161585 and according to ebay is for featherweight sewing machines, which means you should be able to use on the 201. I have a few parts lists and still haven't found part number 161585. I have a "modern day" one but how it attaches to presser bar over the presser foot is shaped differently. I am one that likes the thread cutter on my machines and miss it if it is not there.
I think there may be a couple of tips (in the second picture, underneath the quilting bar ) for the tools that would be used to make the old punched rugs or seat covers made with narrow wool strips.
Smithsonian has the pdf for the Greist attachments. I'm not real good with links but believe this might get you to the pdf --
http://www.sil.si.edu/DigitalCollect.../sil10-215.pdf
Have fun & enjoy the 201.
Janey - Neat people never make the exciting discoveries I do.