Yep! There are deals available on silks you use for magic.
Often I get questions about "thick" or "heavy" silks. (I have been in the import business since 1969.) There are silk rugs available over 5/8" thick and over 400 years old. Making things thick from silk is hardly new! Frankly, making silk thicker usually defeats the advantages of silk. As the importer of magicians' silk, my most basic recommendation to magicians is to use the lightest silk you skill will allow.
You'll find that most pros use 5 momme silk in the 24" size. (Did you know that 8 momme silk takes 60% more space than 5 momme silk? A 24" silk in 5 mommme only takes the space of an 18" silk in 8 momme. To the audience an 18" silk is simply half the size of a 24" silk. Thus it just emphasizes that it is a smaller production or act. Being opaque convincingly destroys much of the mystery that makes the magic, magic.)
Now off my soap box!
If you want thick silks for opaqueness to cover cards, coins, rings, etc., the bargain is at Burington Coat Factory Outlets. There in the Men's shop they are $3.50 each and in some good colors. (Thick silk takes much less skill to sew! The sewing still costs more than the silk. Now you know the importers' secret. If I used thicker silk, I could save money on labor! However, it would not solve problems for magicians.)
The Amazed Wiz