If you can't afford a new CPU, you could try straightening out any bent pins, and manually installing the broken ones into the corresponding holes in the socket, then installing the cpu on top of them and hoping they make proper contact between the CPU and motherboard. I haven't tried this myself, but have heard of it working before.
Here's an old (NCIX) Linus Tech Tips video for example, in which he does just that...
View: https://www.youtube.com/watch?v=EdDccsbv5hA
It might be best not to try straightening pins using random pokey implements like he does though. Using the hollow tip of a mechanical pencil might work better. You'll want all the pins to be straight to avoid breaking more off when reinstalling the CPU. Here's another video showing that...
View: https://www.youtube.com/watch?v=5bjPSH41FRQ
It may not work, but it could be worth a try. Try to avoid bending any bent pins back and forth repeatedly though, as that will tend to weaken them, and could cause more to snap off. And if you manually insert pins into the socket, make sure you are placing them in the correct holes, for the same reason. And of course take your time, to reduce your chances of making things worse. : P
Do you happen to have a photo of how the pins are damaged?
Edit: One other thing I should probably point out is that if you place broken pins in the socket, but end up replacing the CPU, make sure those broken pins are not still in the socket when installing the new processor, unless you want more broken pins. : P You might also want to avoid putting little fragments of pins into the socket, since they might be hard to get out. And if you try this, it would probably be best to leave the motherboard outside of your case while doing so, at least until after you (potentially) get things working. That way, you'll be able to reach things easier, and can turn the motherboard upside down to get broken pins out of the socket if needed. And if this somehow manages to work, I would avoid removing the CPU again unless you are replacing it, since there's no guarantee that it will make proper contact again.