Such a stunning bird the palm cockatoo is I'd love to have one if I could find a breeder who has them
They're rather rare in captivity, even in Australia. The only people who I've known to keep them are zoos (Adelaide Zoo) or very high end avian collectors (generally these people have the money to simulate the natural habitat). There have been some absolutely mind-blowing (larger than the backyard) enclosures for these 'toos, all based around their diet, needs and mental stimulation.
I've heard of a few cases of people keeping them as pets, but many end up being given up to professionals due to their health and
mental demands.
They are crazy intelligent, majestic and beautiful birds. So keeping a 'too like that entertained is insanely difficult, and their noise levels are exceptional. Personally, I'd rather leave them in the care of avian experts

It would just be too sad to see such an intelligent and beautiful animal kept in an artificial environment.
Price wise, I've seen them go anywhere from $16'000 upwards to around $40'000, possibly even more. They're very vulnerable when young, both physically and mentally. If you do decide to get one, be very careful of who you buy from. Like the hyacinth, they're a good 'bait-tool' to unsuspecting owners.