Am chinese, can confirm that Aleh1811's reply in the thread is legit.
If you want the translation to be more nucanced, I would suggest you not use the quantifiler "一只" in this sentence, add "卖(for sale)" and “吗(a modal partical that suggest a questioning tone)” , as in "你(们)有蓝色挪威鹦鹉卖吗?"or"你(们)卖蓝色挪威鹦鹉吗?"
Aleh's translation is no wrong, but feels a bit weird as a native speaker.