There are many reasons the ATF should be abolished, this just being another one.Damn, this is a sad story. Wish the OP well in recovering the rifle, I get being strapped for cash, that's an heirloom gun I'd rather keep in the family and pass down if there's anyone to pass it on to, but I get being cash strapped. I think this makes reason 4,938,328 the ATF should be abolished and all gun laws stricken from the books.
As confirmed in US v Miller 1939 and corrected by DC v Heller 2008, suitability for military use is not a reason for making a firearm illegal or restricted. In fact it is a basis for specifically including military style firearms as part of the God-given right of the people protected by the second amendment.