'78 wiper knob replacement, non delay

I have a '78 without windshield wiper delay but I am missing the knob, otherwise it works fine.  Lots of places sell the delay knob with the arrow but I have had no luck with finding the non delay.  Does anyone know where to purchase one?
I'd put in the delay style switch if it would work like my original two speed just so the annoying bare stem isn't staring at me every time I get in the car, lol.  But given all the other components not included in my early build '78 I doubt it's not a straight forward adventure.
Suggestions?