In this photo of Kevin in his studio, around 2008-2010, what could probably be a Dallas Rangemaster Treble Booster can be seen on top of his set of rack effects.

In the Video (link above), at about 2:50, Brian can be heard telling about how he met Rory Gallagher, who told him to take a Vox AC30 and a RANGE MASTER Boost and turn it all the way up. https://guitar.com/wp-content/uploads/2016/10/Brian-May-Vox-cover-3.jpg On this photo of Mays Rig you can see the Booster standing on the top of his AC30. He used it on the Queen I and II albums (maybe on later ones too) and on early tours. Later he used Greg Fryer Custum Made Treble Boosters.

In this article with Music Radar Tony says, "When I lived in Cumberland, when we did the Mythology thing [Iommi's earlier band], there was a guy up there and I used to use his treble booster called a Dallas Rangemaster to give my sound a bit more 'oomph'."

One is on prominent display throughout Gibbons' segments in Fuzz: The Sound That Revolutionized the World, starting at 3:41. It is also mentioned by Mike Piera of Analog Man on the official Beano Boost product page, noting that Gibbons expressed preference of the Beano over the original.

Billy F Gibbons seems to hold his Dallas Rangemaster in high regards, one of his Holy Grails. In 2008 he called to tell me that his new Beano Boost was even a little better, and maybe the old box was best for a museum. We should hear his new Beano Boost on the album they are working on in 2008, Mr. BFG is always at the cutting edge, with the best tones, while revisiting vintage gear and making it fresh again.

According to this Music Radar article "The Dallas Rangemaster was the other key component of Rory’s simple setup and added bite to the tone from his AC30."

Used on Breaking the Chains, as stated by Lynch in an unsourced interview transcribed in this October 19, 2018 The Gear Page post. Mike Piera of Analog Man quotes the same interview on the official Beano Boost product page.

I love Warren's tone. Warren was a big fan of Dokken's first record. We always talk about this. The European version of the first record which is out of print, has the sound. When I played on that record, all it was was an old Marshall head, an old Super 100 Marshall cabinet with a cane front, and a Rangemaster Treble Booster which Ritchie Blackmore uses. They don't make it anymore. I also had my old grey tube Echoplex that I used basically as a preamp. (...) The American version is not as good. They remixed it and added some bits. After doing six records, that was the best tone I ever had, and I would love to go back and get that tone.

Mentioned in this August 5, 2014 Guitar.com interview.

Guitar.com: When you started playing guitar, what was your favorite?

Tipton: My very first guitar was a Rickenbacker short scale neck. It was lovely to play, but it sounded awful. And so I shopped that in for a Strat. My big hero at the time was Rory Gallagher, and I got a Strat, a Dallas Rangemaster treble boost, and a Vox AC-30. And I used that for quite awhile. And then I got an SG and I used that, so I had the Strat and the SG. And I used those for a long time, until I got involved with Hamer, and had some custom guitars made by Hamer. And I still use the Gibson as well, quite a lot. The necks on my Hamer guitars are caliper measured from an SG neck. I love the neck on an SG.e did a pretty good job of it.

The large enclosure on the left, in this photo of Marc Bolan, is a Rangemaster treble boost.

"I even got a Brian May Red Special guitar and a Rangemaster treble booster" - Mike Stroud

Wolf Hoffmann uses a Dallas Rangemaster, as detailed in the "Behind the Scenes" section on his official website.

Wanting to sound like Rory Gallagher, a 17-year old Dave Gregory purchased a Dallas Rangemaster for ten pounds. On the treble booster, Gregory says "As rubbish as I was, I sounded just like Rory... I couldn't play like him, but it didn't matter: I sounded like him." He later had it wired into his Ram's Head Big Muff (01:28:41).

In preparation for a tour, Warren Defever, known for his work with His Name Is Alive, showcases his gear setup on Instagram. The post includes a reference to a Dallas Rangemaster, indicating its role in his effects chain alongside other notable brands like Electro-Harmonix and Strymon.