I believe that the folding stock can only go on a pre-ba age rifle that had one on prior to the ban. They do make look-a-likes, ones that look like folder but are pinned so they will not fold.
Check out some of the RFC vendors, they have some really neat stocks you may be interested in as well. Also you may want to post something in the "want to buy" section. I'm sure someone has a factory stock laying around that they would sell cheap. Most of us take them off anyways to replace with aftermarket one.