RNK Distributing has a product called Dream Weave which is not actually a stabilizer, but a fabric enhancer. It is use to give light weight fabrics body. They also carry one that is part of the Alex Anderson Quilters Select, when used, it allows quilters to use those beautiful silks.
You may want to look into those at rnkdistributing.com. This quilt sounds like a labor of love. Please post a picture when you are done, it sounds very interesting. Love Game of Thrones, not ready to commit to a quilt, tho.