I'm not sure that any such story actually exists. I don't think there was anything in the Hawks archives at Brigham Young University beyond the script. A widely held view is that it was written by HH's daughter Barbara, although it's uncertain what 'it' might be. He talks about this a bit in the interview he did in Movietone News in a late interview with Kathleen Murphy, although I'm not sure if that can be taken at face value.
From: Film and TV Studies Discussion List <[log in to unmask]> on behalf of Dana Polan <[log in to unmask]>
Sent: 23 September 2021 17:15
To: [log in to unmask] <[log in to unmask]>
Subject: [SCREEN-L] does anyone have the original Campbell story for Rio Bravo
I would like to look at the short story that Rio Bravo is based on. A quick look through google didn't bring up anything. Might anyone have this as an electronic file they could send me?
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