You can check Mantis Miniatures. They are 1/35, but may stand in for a crow at 1/24th, dunno.
It's also not so hard to make some yourself. I tried that with my Atilla the Hun figure and turned out okay I think. Should be well withon your comfort zone, knowing your work.
- start with a ...uhm...avocado-shaped blob of putty, let dry
- shape by filing and attach second blob as basis for head and beak.
- shape head and beak with file.
- add tail feathers on back with lead foil
- smoothen with putty
- drill holes for legs and insert copper wire
- cover wire with putty to bulk up legs
- attach bird to branch with the copper wire from legs
- form claws on branch with putty.
Sounds more complicated than it is.
Good luck.
Cheers
Adrian