I "think", though not positive, that all the non Singer cases use the 1.25" round hinges, while Singer used the 1 1/8" hinges.
When repairing my cases getting hinges is the hardest thing to do. Sometimes I"ll get lucky and the machines I buy that come without cases will have a set of hinges on them. Usually they don't.
Then there are the stamped hinges that break and bend. They are a pain.
If all I had was the 1 1/8" hinges I'd make a filler around them and use them. Not that hard.
Joe