The stock alone is no problem as that does not need anything but insurance to ship, and I'm fairly sure that so long as you did not sell item that a receiver can be shipped for work to be done on it.
In selling just a receiver for a sxs needs an FFL or if 50 yrs or older a C&R, kind of ridiculous.

If you find out that you have to go through a FFL dealer you can go to Auction Arms and try this.
http://www.auctionarms.com/help/fflnetwork.cfm

Last edited by JDW; 01/21/09 01:25 PM.
David