Pro Chemical and Dye has a couple sets of specifically silk paints. The one that looks like it may be useful to you is the PEBEO line with shimmer colors. The directions do say it works on synthetic blends. There are some other concerns that come up like setting the color, but that might not be an issue in your space. Check out prochem’s website, where they carry a really wonderful assortment of products, and their people are really helpful on the phone. Hope that helps!