I found the pattern for my bustle in "Period Costume for Stage and Screen: 1800-1909" by Jean Hunnisett. Model C. It's a beautiful bustle and very easy to make.
Beige cotton and crinoline steel were used. I placed the boning on the outside instead of on the inside, and used plastic boning along the grommets where it laces. The back piece (the bustle part) was made 2,5" wider to make the bustle bigger. I love it.