ISMACS has information about it and has the manual for free download:
http://www.ismacs.net/singer_sewing_...e-manuals.html
I think $40 is a great price! It is a very cute machine, and I'd like to see pictures of the 27 with rose decals. I just got my first treadle, an "Improved Family" or 15 (the first class 15) with apple blossom decals. Looking at your pictures, I think that the extra needle plate that came with it probably came from a 12 as it is a small rectangle. Would you measure it for me sometime?