That frame is EXACTLY what you need of you're wanting to have a rock crawler. The AX-10 is a kit, but it the ARTR is about the same price, is already built, and comes with some upgrades that the kit doesn't have. For the radio, you could probably use the radio system that's on your duratrax.
You would need:
motor and ESC- anywhere from $40 - $200
Battery - $20
Servo- $12 (MG995, 200+ oz/in of tourqe
radio system ($20 to $500, and everywhere in between. A $20 RTR radio system will work just fine)
That's pretty much the only things that you'll need to buy. If you have any questions about crawling, building a crawler, etc... just let me know. Feel free to PM me with any questions that you might have. I'm no veteran or anything, but I have built some crawlers and I've helped several of the members on here get their crawlers and get them set up and everything.