Try Indian Jeweler's supply, and Thunderbird Supply in Gallup. I
think the Spiny rough is around $2.00 an ounce, if memory serves, and
they have cabs avaliable as well. You can search for either supplier.
They also have other kinds of rough shell. Watch out for the dust!
The rough sometimes has tiny little voids from other small parasites
and you really have to watch for those. I have dealt with both and
find service excellent. The usual disclaimers.
Frank A. Finley
Handmade Indian Jewelry