Coquina Clams?

[bigbubbacain]

Does anyone know where it's possible to obtain Coquina Clams? I remember these from my childhood on the Texas coast. They were no more than 1-2 inches long, in beautiful pastel colors, and they were extremely active. They move through the sand so quickly that I'd love to have a lot of them as part of my clean up crew. Has anyone seen these available for sale?

 

[mikchabe]

I tried keeping some a while back and didn't have any luck (they only lasted a few days). I expect that they need to live at the shore line and depend on the wave action. Never seen them for sale in a LFS.