Some may disagree, but I think it is foolish to willingly dive into parrot ownership with a hard limit of "I only want to spend this much". Even if you get the bird for "free" and get a cheap or free cage... feed, vet costs, toys, and other hidden parrot ownership costs can easily go beyond this amount.
Most avian vets cost between $40-100 just to walk in the door. A new parrot should ideally have a wellness exam yearly, and the first exam should include a blood panel and fecal swab. You are looking at probably a few hundred dollars right there.
What happens if the bird gets sick? This can be wildly expensive, and for an intelligent and long-lived parrot you owe it to him or her to try to aid them with medical care.
If you need to buy a cage, consider the amount of time you will have the parrot out. If it's less than most of the day, you need to get the largest cage you can afford. This can be $500 for a medium cage, and over $800-1,000 for a large cage. Macaws need LARGE cages unless you are able or willing to completely commit a room of your house to the parrot to be out in during waking hours. Aviaries are an option, but only in some climates, and carry the risk of predation if they are not well constructed.
Macws and other parrots chew-- a lot! Now, there are ways to save money here by constructing your own toys, but it's very important to use toy parts that are non-toxic to the bird. This can be tricky. Even if you build your own though, you can expect to need to replenish toys fairly often. For individual birds, it can be from one to 10 or more toys per month. Parrots love to chew and forage. They are intelligent and need things to occupy them.
Just some considerations. Whenever someone would approach me with "I have x dollars, what kind of parrot can I get with that?" I would always tell them to go home, put the money in savings and keep adding a lot more, and research in the meantime.