KH Caliper Bolt - what do I have?

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So I thought I had two original KH caliper to spindle mounting bolts, so I ordered two more new reproduction KH bolts from a FABO member to have a complete set for my Barracuda disc brake upgrade. In the picture the left bolt is the new reproduction unit and the right is one of the two I already had and thought to be original. The reproduction bolts are very nice and fit in the caliper hole a bit more snug than the old ones. I measured the shoulder of the repro bolt and it is slightly wider. You can see in the pic that the repro bolt has more shoulder length, less thread length, thicker head, and is a hair shorter in overall length.

This is a bit of a curiosity to me, can anybody tell me whether my old bolts could be original? I came by these two older bolts from a fairly complete KH setup I purchased from another FABO member.