My iPad is bent.

My daughter-in-law was given an iPad mini in a similar condition. In her case the screen was cracked due to the bend, so I did all my homework in advance, including purchasing a replacement screen and figuring out the price and availability of rear housings. As it turned out, once I had the screen off I was able to bend the screen back into its proper shape so I didn't end up needing to replace the entire housing.

Is your screen broken? If not you'll need to be very careful removing it so you don't end up breaking it in the process; use plenty of heat and practice patience. Once you have the display off then you can evaluate whether you can straighten it or not. Use a metal ruler to gauge the flatness of the housing as you straighten it. When I did mine I didn't end up needing any tools; the aluminum is a soft enough metal that I was able to bend it by hand until it was back to being perfectly flat. If there are any corners that got bent in you may need to pound those back out to refit the screen in; I had to, but if your screen isn't broken you may not need to worry about that.

If the frame is too badly bent and no longer usable then you'll need to replace the housing. You can probably find them both new and used; generally it'll be easier to work with a used one that still has some of the parts installed, but you may be able to buy a new housing that has the small parts included. Either way you'll most likely need to gut the entire tablet and transfer most or all of the parts to the replacement.

Hopefully that'll give you some food for thought; feel free to ask if you have any questions.