Where can I find the gasket of my new hamilton beach blender(wave station)?

The manual says I need to use the gasket. But, the company did not send any gasket in the package.
what do I do?
It is not assembled.
I ordered it from amazon

Is the blender jar assembled? It will be between the jar and the blade. If not, you can contact the company or take it back to the store. If you don't have a gasket, it will leak.

Add...it should look like the gray circle laying on top of the blade in this picture. http://www.bing.com/images/search?q=blender+gasket&FORM=BIFD#focal=e327462cd7d1a588ae09021ccdfb0cce&furl=http%3A%2F%2Fimages.bizrate.com%2Fresize%3Fsq%3D220%26uid%3D467055449