Please help identify these drop spindles

[brossow]

Picked up these drop spindles back in 2004 and intended them to go on my '64 C10. I'm going to repurpose them for use on my '72 instead. Problem is I can't remember which vendor they came from originally. (I bought them secondhand from someone else and now I can't remember what he told me.) Does anyone recognize them? I need to know (I think) so I can be sure to buy the correct ball joints when the time comes (and maybe for other reasons as well).

I can get more pictures if necessary. These are just a couple I had access to from work that showed the markings on the spindles, which simply say "C-10 RH" and "C-10 LH" and the back side of a spindle.

Thanks in advance!

Brent