Hi Janceejan,
I am one of the authors of String Quilt Revival and am sorry you are having a difficult time finding the 30" wide no show mesh stabilizer. Unfortunately the publisher would not allow us to promote our product in the book. You can find the 10yd, 25yd and 50yd bundles of 30" wide stabilizer on our website
www.stripsandstrings.com at more reasonable prices. Please be careful about using the tearaway stabilizer unless you plan to remove all of it. Muslin has been used for many years, but it has a bias and stretches and ravels. A lot of our patterns are worked on the bias and would be distorted when worked on muslin. Sorry for your confusion and hope this info helps.