Quick collage idea, using an image of blondie from the 70s, could be painted in a simple stencil style or realistic???? Layered with original posters from new york in the 70s and graffiti tags, as mentioned would be great to fade and age the art so its not all so bold!? Also be good to add some more abstract shapes and patterns in the background.
Maybe include images similar to these, can be painted in different styles, realistic or stencil mixed with other images like the graffiti tags and layered with posters etc.