What's the current wisdom on recovering pumping bellows and reservoirs?
I have old cloth of the appropriate weight that I bought when I started
work on my Aeolian reed organ a decade or more ago; it still feels like
new, but I have obvious reservations about starting with cloth that
might be 20 years old.

I've been told that new cloth will not have anything like the longevity
of the old cloth that I used before and that I should leather the
bellows instead.  Leather has long been the standard it seems for organ
work and motorized pumps.  Is that what folks are generally doing now
for foot pumped player piano-like instruments?

Cheers,
Roger Wiegand
Wayland, Massachusetts
http://www.carouselorgan.com/