This is the Univox Hi Flier famously used in the encore of the Rio De Janeiro show. Video of "Dive" can be seen on the Live Tonight Sold Out video and also below.
According to Kurtsequipment.com
"Univox Hi-Flyer, mahogany neck and stock single coils at the Rio show encore. Kurt liked this one too. Later got a humbucker in the bridge"
The humbucker in the bridge alteration can be seen in the latest photograph above (by Geoff Moore) as well as the show on 7/23/93 at The Roseland in New York City.
Geoff Moore is the photographer that shot most of the photos for the Cobain Unseen book. He was the sole photographer allowed to shoot the guitars that are in the Cobain estate vault. This guitar was not featured in the Cobain Unseen book. For other guitars photographed by Moore please visit the "Geoff Moore" tag below, as well as Geoff Moore's website.
Note: There is another Geoff Moore photographed Univox Hi Flier that ended up in the Cobain Unseen book. Entry coming soon.