American made HD Diamond series lower ball joints
http://shop.rareparts.com
I tried to paste the link to the actual page for 57 Fords, but I'm having assorted issues since I downloaded the new updates for Microsoft windows. You'll just have to wade thru their difficult to maneuver website. The diamond series lower balljoint is about 148. EACH, but at least they're making it.
Rich, I couldn't get your link to load but this worked
http://rareparts.com/
I'm trying to recall is these are the people who bought the MOOG tooling?