Where to find shells?

[Mermaid Crystal Shimmer]

Hi All, I was wondering where do you get your shells (the big ones used for tops etc)?
I want to create my own tops but I can't find shells for a reasonable price. And how big do they need to be to cover up b cup size?

[Mermaid Fenicia]

If you want, I have some big plasticshells perfect for mer-tops ;) They cost only 10 euro + p&p ;) They are the same shells as in my tutorial: http://users.telenet.be/the-mermaid/tutoral/schelptopje/sheltop01e.htm

[Mermaid Crystal Shimmer]

Looking for real shells, prefer bulk. Want to create more then 1 top, and experiment with colors etc =)

[Ariel-Starfish]

I got a few from my aunts after they ate scallop.