Take it to a gunsmith and have the headspace checked before you fire it again.
You can buy stock parts here.
These guys sell parts are and are reputable.
http://www.fulton-armory.com/Foreend stock 30 bucks, you may need the hardware too.
Gas cylinder, new 199$, used good 129$ (this part is critical to how the rifle will work)
New barrel 275 to 325$
They sell several books on the M1 that are must haves.
Looking at the pic again your going to need a whole new stock and front site at least. I would strip it down and carefully check the reciever to make sure it hasnt been welded back together from two different receivers. There is an FAQ on the Fulton site that talks about this, and how dangerous a reweld is. Make sure its safe before you shoot it anymore.
They are great fun though once you know it's safe.
Whoever did that hack job to a wonderful rifle like that should be ashamed of themselves. That's like chopping up a classic car... And you can make them damn accurate without messing with the way the stock looks. I would not trust that rifle until it was checked out by a pro, who knows what other amature crap was done to it it. It could blow up in your face.