need something between 11-12 inches. keymod would be incredible, But I can't find any. something light would be nice.
I know larue will work, and the sws (noveske style) works, but what are some more light weight options?

This is lightweight and keymod -  http://www.midwestindustriesinc.com/index.cfm?fuseaction=category.display&category_ID=1236

https://troyind.com/products/alpha-308-lp-12-blk

Odin Works makes a 12.5" 308 KMod forend. https://www.odinworks.com/category_s/1867.htm

OP, just understand that a standard rifle length handguard is going to be almost exactly flush w/ the end of a muzzle of a 12.5" barrel.  If you want easy acess to the threads to use steam pipe tape to secure a direct thread suppressor, or if you have a suppressor like a surefire socom where you have to access the rear of the suppressor to add/remove it, you will need you handguard to come no further forward than the shoulder of the barrel.  So, you might have to grind about 1/2-3/4" off these.  

I like that odin works HG weigs about the same as the MI...but I'm not sure that fits an aramlite?? Seems like it might be for KAC/DPMS low or high receivers.  Remember that armalite and KAC/DPMS type large frame ARs had different thread pitches on their upper receivers.

Probably you should post up in the armalite sub forum rather than the variants sub forum.