So, just buy some scrolls of Raise Dead and hire a rogue to cast them.
...
I get the point about it getting repetitive but I don't look at it as being that different from delving into different dungeons. ...
And if you are going to have a zoo with sentient creatures, then guess what, morals and publicity go out the window as you are dealing most likely with a totalitarian state - and what the King says is law - there is no worrying about who thinks what. After all, if the King is putting so much money and resources into such a zoo, then he has more than ample resources at his disposal to allow for the "reinstating" of life into exhibits of value. Consider it part of the maintenance costs.
I'd tend to think of such a set-up in the same way as how Caligula managed his empire. He did many outrageous things that the common folk loved. To them he was a fun and entertaining emperor. But, to the aristocracy, he was a living nightmare. Where that all goes is that he had power and money - he could do what he wanted. A King in this scenario is very similar here.
No offense @Dozen , but if I recall, the OP was asking for opinions, not someone to DM the game for him. Everyone here has been posting their opinions and you have done nothing but malign them. Let the OP, and presumably the DM, make the decisions for his world based on ideas as presented.
Saying so is easy. Disprove my reasoning. Go ahead, and take your time.My point stands.
And Dandu's point is still valid.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.