I was surfing YouTube and came across this video of a budgie doing an incredible imitation of R2-D2. You just have to listen to this for yourself. This is just the cutest thing ever. It gave me a good chuckle. I knew budgies were incredible mimics, but I never knew they were capable of anything like this.
That’s a talented mimic, for sure, but it’s worth mentioning that Artoo-type sounds are actually pretty close to the sort of noises that budgies naturally make.
I did wonder if the sound (and appearance) of budgies had actually been an influence in the design of R2 - (apparently not) more details in this thread:
Here’s a link to (more or less*) natural budgie chatter: Budgie Sounds | Parakeet Sounds - YouTube
*As a past owner of budgies, I can recognise a few fragments of human voice mimicry in the above link.
(Sorry, but it has to be posted.)
These aren’t the budgies you’re looking for.
They’re on Dantooine. Your budgies are on Dantooine. 
Don’t call me a mindless philosopher, you overweight glob of grease.