I feel like there should be cover for the blinker rod. Some type of rubber accordion like the clutch boot.

I had a high beam switch that was all jacked up from UV exposure, picked up a spare column that came with semi new combination switches, id like to keep them in better condition....

Here is a picture of a replica 250 GTO that some dude was building.

 

 

No, there wasn`t a cover for the signal hole but it would be easy to make a rectangular strip of rubber sheet, punch a hole in the center, slip it over the signal rod and tuck the rubber inside. Just make sure that it is long enough so you don`t see the ends with the signal engaged.