Here's a cut and paste from one of R.P.'s posts on another site:
I offer gunflints that I make from Missouri flint I collect locally. The flints are white to gray and rough, tough, and sparky.
Flints are generally 1/8" longer than wide, so a 5/8" wide flint is 3/4" long; same for other sizes unless you need something special.
5/8" wide size are $10 per dozen
3/4" wide or 7/8" wide are $12 a dozen
1" wide or 1 and 1/8" wide are $15 per dozen
I limit folks to 3 dozen of any individual size per order so I can supply all customers. Shipping and handling runs $1 to $1.50 per dozen, depending on size and quantity.
Here is how to order: send me an email with "flints" in the subject header. Give me your name, address, and what you need. I will pack and ship with an invoice. You try one in an unloaded gun right away. If they are satisfactory, send me a check. If not, send them back.
My email is rpierce@dom.wustl.edu. I prefer email to private message, but can work with you if you prefer PM.