I have a standard hazard switch placement in my truck, below the steering wheel. So I could easily put the SDO Carling switch in place. It's very nice! My truck originally had a blank spot where these three switches are on the NAS 110s, and the dash panel that I got to replace my broken one from 1988 is an actual NAS dash panel; it has the three NAS style switches intact, unused.
I can see why he does not want to go over to the SDO type switch. The wiring would be a monster (it is not a simple on/off wiring set, and it may not be compatible with the NAS harness.) and the Carling switch simply would not fit that spot, nor would it look any good there.
The switches seem robust enough, but I could imagine that over time and use, they could have internal problems. I'd pull the dash (not too difficult, just be sure, 100% sure, you have it 100% unscrewed in all locations before trying to pop it out from the top edge first.) and double check that switch, even try to open it up to fix it, even take it to some kind of ninja monk expert to try to fix it, before actually trying to find a replacement.
Your only other option is to buy from someone like me, but I'd need to figure out a nice way of patching the hole before I'd let it go. But hey, make me an offer, it's just sitting there looking pretty right now.
