Wow! Antique-shop.com forums are in the big #1 spot on Google for the search term "antique shop forum", for 4 years running!Thanks to YOU.
The hings size/configuration does matter!Maybe give this place a shot! Never used them but have seem them referred to on some sewing sites.https://www.theoldhardwarestore.com/product/flashed-copper-sewing-machine-hinge-pair/