Where can I get a G.I bolt for my AR-15, mine blew apart this weekend. Barrel extention and carrier both look fine upper shows no bulges. It just took all the spines off the bolt. A friend thought a goverment bolt might be stronger. Any thoughts on this.
Red

You should get the weapon checked out by a gunsmith. Bolts just don't "blow up" for no apparent reason.

Still under warranty?  Oh, and you sound WAY to non-chalant about this.  I'm not trying to be a smartass or anything, but you basically said "My gun just blew up in my face and now I'm going to stuff new stonger parts in it and hope it doesn't happen again."  What happened to your gun is serious critical failure.  You need to figure out why it happened before you even think about putting ammo in it again.  KB's happen for a reason.  Is it gas system related and failed to unlock the lugs, was there a bullet in the barrel from the previous round?  A lot of guys here are far better at troubleshooting than me, they should be able to help more.  It sounds like you got off lucky.  

This just happened to me 2 months ago.
I sent my upper into Bushmaster and they fixed it for free, all they sent back was what parts they put in.  All that was listed was a bolt.  
I'd definately say send it back to manufacturer or to a gunsmith.
I was never told what caused it, maybe bad forging.

Maker of bolt?