I just ordered an SMI bolt carrier group (complete) from Whitestone Castle Armory (WCarmory.com). $97 !!! And they have them in stock. They ship all over the US and accept "walk ins" by appointment. I have heard glowing reviews locally on them jso thought I would give them a try. ps: they also have powder and primers in stock. VERY reasonable prices. They apparently have a number of sources for loading supplies and accept back orders.