As far as I know, no one "makes" the upper arms. They are built using parts (bushings/shafts) from different sources like "Moog" or "Doorman" etc. and good cleaned arms. If someone has started making them that is news to me.
i already bought shocks and coils but i still may be money ahead to buy the whole kit 1971-73 SUSPENSION RESTORATION KIT SB http://www.laurelmountainmustang.com/products/1971-73-suspension-restoration-kit-sb
the front suspension kit came in. they are definitely not MOOG parts but for the price you cant really beat it. i was kinda bumed out when they didnt include the lower control arm bolts, and the upper control arm bolts are coarse thread (didnt include the nuts for those either) the upper control arm bolts are shorter than the o.e. ones so thats a plus but im still going to cut them down a bit to get a little more header clearance. The sway bar bolts that they give you with the kit are a joke to look at. but then again i have a pair of MOOG, and some ADDCO one to compare them to. No nuts for the perches either. So im going to order new LCA Bolts and get a few lock nuts and loctite for the Uppers. will take close up pics of the parts if anyone would like. Im keeping the original stuff so when these wear out i can rebuild the originals.