Have you seen these? (Not sure if these work with a Daniel Defense mount.)
Burkett's mount (Out of stock now but other vendors may have them.)
http://www.mattburkett.com/shop-onli..._id=3&vmcchk=1
Also, AMS Machine in Carthage makes a mount as well.
http://amsmachine.net/index_files/Page423.htm
Yankee Hill makes an offset, too.