Is it your radio or your speakers that have malfunctioned? If you have inbuilt speakers then swapping them without damaging the car is hard. Swapping the radio and keeping the existing speakers would be easier and cheaper.
I agree, it's important to know what is damaged exactly before you go and rip everything out, just in case the damage isn't as extensive as you may think.
Thanks for your input guys. I had the same thoughts but after getting everything checked, I found out that the radio wasn't actually functioning (though it's given me service for quite some time). I don't even intend to do the 'ripping off' on my own.