I can 3D print such a thing very easily, but without access to a CNC mill its practically impossible to produce it in steel given the cost and time constraints of fixing an exhaust system ;)

Yes, I was inspired by your boot grommet fix. +++

Another excellent engineering piece from MJ!
Keep going!! +++

Though I've had another idea that would be much easier...… :cool:

Make your piece as originally designed, 8mm maybe, but drill 6 holes - 3 each on opposite sides. 2 identical pieces for 1 joint.
Then make 2 cuts to create the piece shaped like mine and retain the cutout segments which will have one hole in each.
Fit the main pieces over the pipes from opposite sides, insert the 4 corner bolts and tighten enough to hold in place.
Then slide in the two sections previously cut out and fit 2 further bolts to make a complete fitment. Tighten.

The repair pieces might need to be slightly larger or a subtly different shape to accommodate the extra bolts. More Hexagonal maybe, like the attached sketch?

Weirdly enough, I was thinking along the same lines in the early hours as I was trying to get to sleep, after seeing your first diagram. Would I be right in thinking that you mean placing one part on the pipe in a U position and the second part on the other side in an upside down U position?

Spot on Sean. +++