Digital BW, The Print

By chance I clicked on "What's New" at Digital Art Supplies

http://www.digitalartsupplies.com/whatsnewatdas.html

and found that they are selling 9"x35" and 11"x35" sheets of 
Schoellershammer Velvet:

Schoellershammer
Velvet 300 - 
Panoramic 9"x35" - 10 Sheets SHV300P9-010 $41.95

Schoellershammer 
Velvet 225 - 
Panoramic 11"x35" - 10 Sheets SHV225P11-010 $57.95

Not as large as I would like but it is at least longer than 19" and 
you could do panoramas up to 1:3 or almost 1:4. I have not tried the 
Schoellershammer Velvet yet but others have had good things to say 
about it.

Martin