Aren't the upper control arms interchangeable with early Mustang parts? Maybe like the '67-'68 model years?
National Parts Depot, has everything you need, if it's not Moog, it's usually excellent quality. 68-73 Mustangs use everything the same, except for the strut rod.
You are correct that Moog does not sell the upper contrl arms. I was only generalizing about quality parts. Some TRW parts are still available. We sell them every day at Advance. If a warranty issue occurs, Moog covers the warranty. I bought some TRW lower control arms this past year from Advance. The uppers I have came from NPD. Like Dave Boyer said, they are good quality and I installed one on the Sprint Maverick, same as a Mustang. We carry many Federal Mogul companies' parts at the store. Jim