Do you have any friends at work/relatives who may be able to care for him in their homes while you are gone?

I don't know how tame/friendly he is but perhaps he could be "borrowed" by a family who are thinking of having a bird in their house - this way they get practice without the total commitment. But of course the "practice" is on your boy!!

If you do leave him with someone be sure to have something written to say if he needs vet care they should get it and you will pay all costs - that way all angles are covered.