Yeah, I'd hoop the water soluble stabilizer then use a spray adhesive to affix the silk to the stabilizer.

There are two kinds of water soluble stabilizer - one that looks like cellophane and one that is fibrous. Both wash out very well and don't discolor the fabric.

I would use the fibrous kind if I were you. The cellophane type is mostly used as a topper to keep the stitches from sinking into the fabric's weave.