I'm no great expert at much of anything, but there is a downloadable, printable on ISMACS titled The ISMACS News Guilde to Singer Ornamentation Sets. It is 51 pages, but if you print it, it could be bound in a 3-ring binder. I keep the stuff I've downloaded for reference in page protectors and in a three-ring (d-ring) binder. It protects the pages and keeps it corraled (spelling?) in a findable location! Of course, this isn't going to help identify the vintage machines which are not ornamented with decals! Just a "for what it's worth"!
Jeanette