Here's the link for ya:
http://www.gorillamaxx.com/gmx07-replacements.html
Looks like the front skid plate will cost you $24 plus shipping. And if it isn't bent, the top servo plate is $26.
I did the same thing with my G2 when I had it. Just make sure it's the G3R chassis, the first price list is for the Maxx, just scroll down.