I tried one vet nearby, but she did a physical exam and ran no tests. I really thought blood should be taken, but she thought it was unnecessary. I didn't go back there.
Another local vet seems to take blood from conure sized birds by clipping a nail short. This seems like it would hurt more, and for a longer time, and for an animal who sometimes stands in its own poop, it seems like an invitation for infection. So I didn't really want to try that place. My vet gets blood from the neck or from the leg of my green cheek easily. Seems like a better way to do it, although it probably takes more skill and more practice on the small birds.