Safehaven parrot rescue.
All stars parrot rescue
You can look on gumtree, local Facebook groups, bird trader ect to rescue some out of bad situations
You can try rspca or local welfare organisations, they do get birds in on occasions.
Our rescues operate a little differently, and sometimes you have to pay membership fees as well as be a member for at least a year. Most of the birds are in Foster homes so it might be difficult to get hands on experience with multiple birds.