Sheluma

Mike, I saw that, but I thought $26 was kinda pricey for a slide plate. But I'm cheap. If you're not in a hurry, you can try the part number 66525 in a title and description search (did that already, no go), and save the search so that ebay will email you when there are new matches. (Ebay now calls it "Follow this search", if you have the same version I have at the moment. They just changed it, and they usually have several versions floating around, so yours might say "save this search".) Then wait. I would also do a title-only search with terms like "Singer 101 (slide, plate)" and eventually a cheaper one may turn up. Don't use the quotes but do use the parens. The words in the parens are either/or. You will get some results that are not the slide plate but not too many. Personally I would also add (part, parts) to the terms in parens. There will be a lot of results but after the first search there won't be too many more because a lot of them are buy-it-nows that stay for 30 days. Clear as mud, right? I included some examples below.

I found this in completed items. Interestingly the part number for the slide plate here seems to be 66524.
http://www.ebay.com/itm/Singer-101-P...-/181226227241

So, my searches would be:
(singer, simanco) (66525, 66524) <----[check the box "Include description"] and
Singer 101 (slide, plate, part, parts) <---[title only]

If you're ambitious you can search Singer 101 (slide, plate), including description, but search only in Crafts, Collectibles and Antiques (too many results if you search all categories). That's 3 more searches. I would do all 5 searches and save them (aka "follow them")