FYI & FWIW: Brooks is not the only tensioned leather saddle manufacturer.

Berthoud
Lepper
Persons
Sella Italia
Selle Anatomica
Selle Monte Grappa
Tops


Gyes
Cardiff, made by Gyes
Rivet, manufactured by Gyes to their specifications
Velo Orange, made by Gyes


Dia Compe
Papillionaire
Torelli

(I suspect the Torelli, Dia Compe, Spa, and Papillionaire saddles are also made by Gyes.)

Ideale - out of business, sometimes available on ebay or at cycle jumbles

No connection to any retailers mentioned, examples only. There are plenty of places to get any of these.