What Alan Handl has said specifically is that the SCAR 47 is to meet requirements for the military program first. To show the viability of the whole program, this includes 300 blk, 6.8, 5.56, the LMG and of course 7.62x39. Then the 8 shops say hey we will take this # of x, this # of y, this # of z and we dont even want A or B. This is after NSWC crane tests it (Handl tests it in excess of those standards internally but NSWC Crane still must sign off on it).
The price point of offering a 7.62x39 conversion kit to the civilian world is far too high right now, they just will not sell yet. The question was asked of AK owners, http://www.m4carbine.net/showthread.php?147939-AK-owners-gt-gt-gt-is-this-worth-anything-to-you but @ $1500 or so a pop (at current scale) for a gun that is already $3000 might mean not selling alot of them. The issue is the premium that FN puts on its guns and parts make every thing else exponentially more expensive. Until scale can dictate lower price points.
There are plans in place to really cut those numbers down, but caliber conversion kits are not the main effort right now. They exist, they work beyond CAR-H standards, but they would be a net loss at current scale. But they will come eventually.