Me again. You might enjoy reading/viewing this post.
http://edsmum.wordpress.com/2011/01/...-darning-foot/
Here are some for sale but Yikes!!!, they want a lot of money for them especially the flat darner.
http://www.april1930s.com/html/singe...paniments.html
At the bottom of this page is a review on the sock darner:
http://www.newenglandsimpleliving.co...mentsinuse.htm
Well, you really got me researching these darners. Hope some of this helps especially the last review. Again, it looks to me like it depends on what kind of darning you want to do .... socks or fabric pieces (shirt, pants, etc.)