front is different size than the 2 rears. following joints have them as well as still active part # with H-D:
west marine
clampco.com
ASB
gardner-westcott
I measured rear straps: strap diameter when clamped is about 185 mm, strap width 3/4 in, thickness about 0.025 in, bolt thread size 1/4-28, nut hex width 7/16 in.
This is strap with closes sizes to the rear strap I found on McMaster, but it looks like it a little bit smaller than it supposed to be https://www.mcmaster.com/#5312K22