A few studios that feature the same style of models:
-Helix Studios (8TeenBoy is the substudio you would want from them, but majority of their models are seen through most of their substudios).
-Not sure if they're still around, but Dolphin Entertainment was another
-DoggyBoys (no its not related to animals, or kink - that's what the site used to be called). Last I heard they were revamping the whole site, rebranding etc, so I'm not sure what to look for now.
-BoyCrush aka BareTwinks is another.
There are a ton out there, just can't remember them all off the top of my head.