Larue is a good rail, one of the better ones along with Daniel Defense and PRI that are in that $250+ range.
Viking Tactical has very light Extreme rails for a little less money then there are so many cheap rails I wouldn't know where to start.
Sounds like you already have a good choice
The 6.8 is the fastest growing cartridge and #1 choice for hunting deer and hogs with an AR15.
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