Well..... silk thread is expensive and few people buy it, so I've only seen it in very limited colors and quantities at a few of the local quilt shops in my area.
However. If you are using it for hand applique or something similar, may I suggest you try Superior Thread's Bottom Line instead. I bought an assortment of different colors on prewound bobbins, and it blends and sinks into the fabric as well as silk, at a fraction of the cost. The bobbins came in a handy donut bobbin holder.
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