Welcome to the Armory Panther,
Need some clarification on your rifle, is it running a Carbine, mudlength or Rifle length gas system?. Does it have the Front sight post I ask because if you want to mount a free float rail, it will have to be unpinned and removed. If the handguard(s) you have now are the two piece, then the Delta ring will need to be removed as well in order to mount a Free Float rail.
You can find Handguards at;
http://www.joeboboutfitters.com/Samson_Evolution_Rail_p/sam-evo-rail.htm I put this link in because this is a great rail at a great price.
Bravo Company USA
Let us know what you have so we can give the right input.