I made a bellows for my 8x10 Eastman 2D. I used white blackout curtain material (ensures light proofing) on the outside, and coated this with thin nylon. I was able to find the nylon in pretty much any color, and got one that was a close match to the original red/maroon bellows. Both the blackout curtain (mostly available in only white) and the nylon are thin, so you dont have to worry about everything getting too thick. Inside the blackout curtain, I put the black cardstock ribs, and covered this on the inside with a thin black cloth. This "three-ply", all glued with 3M spray adhesive, has worked very well. I have a bellows that fully compresses to allow folding of the camera, and can extend to 30". All of the materials are readily available at any fabric shop.

it's a lot of work to make the bellows, but very satisfying when it's done.