Hi Richard,
I thought long and hard about the control horns. I ended up constructing them from a few different parts.
The base, though not completely accurate, are photoetched exhaust header flanges for an automobile exhaust system. PE bolt heads, of course. I believe they are from Model Car Garage.
The main part is a round toothpick, split part way down the middle, and the end of a PE control horn is CA glued into the split. This part goes through the base into a hole in the tail surface and epoxied in for strength.
The PE control horn is from an Eduard PE sheet of control horns and flying wire tensioners. I cut off the top of the PE control horn for use in this assembly.
I made six of these, so the process can be repeated somewhat consistently.