There’s no doubt the repairs will cost a bloody fortune. I could see .4 or .5 million by the time it’s done, not that I am any expert on it, it’s just that kind of work is astronomically expensive.
The parts are reproduced these days and believe it or not are not that expensive. I am in the business BTW. That A/C was extensively rebuilt not too many years ago so its not that big a deal really. Your price guess is pretty close BTW.