WOW! Nice list of leather sources, Gordon. Do you (or anyone else on here) have any ideas on which leathers, besides chamois, is soft and flexible enough to make good Panoram bellows? What about dying it? What about sealing pores to make the bellows light tight . . . and without making the bellows stiff?
By the way, is Tandy still around?
Columbia Organ Works, Inc. has the best choices of leathers for making leather bellows, and I would thing that you would measure the thickness of the old leather to make sure you order the same thickness. The XXX Extra Thin weight leather is only .005 - .007" (0.18mm) thick and other leathers are .030 to .050 inch thick (.762-1.27 mm) or even thicker.