Bolt carrier groups have become much easier to find as of late without resorting to Gunbroker.
PSA has them in stock now. They are, for all practical purposes, identical to the BCM BCGs, aside from the markings. They likely come from the exact same supplier as the BCM-marked versions. The price is still about $60 higher than pre-election prices, but at least they are out there.
http://palmettostatearmory.com/index...ier-group.html