Where to buy a superconductor for a magnetic levitation model

[CAN111]

I have to complete a project in a weeks time but i am missing a vital part to the project.
I am building a model of a levitating train and have all the magnets and tracks ready i also have liquid nitrogen ordered, unfortunately i am unable to find any form of superconductor. Any help is appreciated. please tell me about any stores which may sell superconductors or a substitute which does the same things.
thanx in advance.

 

[nbo10]

http://superconductors.org/Play.htm

 

[stefano5010]

Hello,
I want made a project like yours, can u send me detailed information how u made your work (magnet disposition, stability control and so on).
Thank you
Stefano