I found a box of the original type sway bar mounts. They are made from aluminum.
We have:
1 set of 1"
3 sets of 7/8"
1 set of 3/4" (The size we normally use for our front sway bars).
1 side only of 1/2"
1 side only of 13/16"
1 side only "not drilled"
These for $75/set. I'll let the sets go for $15. I'll let the ones that only have 1 side go for $5 each.