@JGshooter
The way your rifle is built right now, you have one very simple option that would require ZERO gunsmithing.
Get the Magpul MOE handguard, and install the alum/poly rails to it. It takes rails at the 1, 6, and 11 o'clock positions (12 too, but the Magpul 12 is the wrong height to match a receiver). The Magpul MOE handguard should be a direct replacement for the handguard you have on your AR10 now. Looks like you'll need the Mid length HG. Total cost maybe $50
For any decent rail system, you can expect a $200+ bill. MI makes some cheap ones, but they are just that... cheap. You didn't spend all that money on an Armalite just to start cutting corners now, did you?