Custom MediaElement

Question

I am currently using some MediaElements in an application I am creating. I am dynamically creating them and adding them to a wrap panel.

The problem is I need to be able to add a key to them so I can go back and locate a specific one.

I was going to inherit from the MediaElement and just add the key as a member. Unfortunately I can't do this because it's a sealed class.

So I tried to create a class containing a MediaElement and the key but I can't add that to the GUI since its not a UIElement.

Is there anyway I can do this? I just need to be able to add MediaElements and them be able to go back and find them later so I can modify or remove them.