Have you tried this yet? It is my favourite thread for hand appliqué. The 100wt thread is so fine it disappears into the fabric. There are 200 meters on each spool.
If you want to save a bit of money consider buying a YLI silk thread spool collection, Elly Sienkiewicz, Pat Campbell, and Jeanne Sullivan have put together tubes of seven spools for a good discount. Or you can buy an assorted collection of five neutral colours which could take care of all your appliqué needs.
Want to know how to use YLI silk thread? Try the free illustrated tutorial with step by step instructions - How to Appliqué.
This thread is 100% filament silk, 2 ply, tex 10. Use Microtex 70/11, or embroidery 75/11 needles in your sewing machine. If you are not using the silk in your bobbin then use 50 or 60wt cotton.