New crown needed

I have Bulova Accuquartrz for which I need a new a new crown. I need a dustproof or semi-recessed gold crown.

The number on the case is 7578-1 and the number on the back is 3 726037 N4

Does anyone know how I can find a part number for the crown ? Is it possible to fit other crowns on my watch ?

Here is the watch http://www.mybulova.com/watches/1974-accuquartz-3745

Thanks

John