Crisis on Infinite Earths #7 comic book from DC Comics
I still remember how shocked I was that Supergirl died.  Not as shocked as I was later when Superman died, but still shocked.  Yeah, she was a bit player in the DC Universe, but she was one powerful back-up. 

       

This is a scan of an old comic book. This item is not for sale. But you can find it on ebay.
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