I bought some back clamp attachments at a yard sale, as they said they would throw them away otherwise. I didn't have a machine for them, but knew that there were machines that took them. Several years later, my brother and I refurbished the treadle that may sister learned to sew on. As it turns out there were not any attachments for the 66-1 treadle, so I dug them out and they went to her. I have since gotten a 66-1 and have picked up a few attachments for it. One was a ruffler that was in with another bag of attachments. You may find some in thrift stores, yard sales, ebay, etsy, offerup, etc.
As for the top clamp hemmer, WIChix is right about a variety of machines that took them and a variety of sizes and dimensions. There is a chart on treadleon.net that gives some of the dimensions.
https://www.treadleon.net/library/topclampingfeet.pdf However, there may be other machines that it might fit as there were many, many machines that have a different name on them other than the company name that actually made the machine. There are even some New Home machines that took top clamp attachments.
Janey - Neat people never make the exciting discoveries I do.
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