1 of my 360 got banned can i somehow get a broken

Unfortunately, you aren't just hardware banned, but IP banned as well on the Live network, typically. But if you think you can do it, try and swap out the network adapter from a broken 360 and put it in the one that got banned.

But bypassing a ban isn't a suggested thing to do either. I'm not responsible for anything that might break for your opening the console without prior electronics knowledge.