Skimming through the Monster Manual:
Macetail Behemoth (Anklyosaurus)
Bloodspike Behemoth (Stegosaurus)
Feymire Crocodile (Deinosuchus)
Spiretop Drake (Any small pterosaur)
Guard Drake (Any small therapod)
Needlefang Drake Swarm (Compsognathus)
Rage Drake (Velociraptor)
As for homebrews, I got nothin'. Not a bad idea, though; I'll see if I can't whip something up tonight, just out of curiosity what they would look like.