That is the same switch that my 56 came with when I got it. It is original and still works well.
Truck Shop and others sell that unit.
It was also used on 54 cars, Corvette's, and available on trucks from 55.2 through 59.
The hose clamp is a not an OEM option.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine