If you are referring to the device that attaches to the passenger window, it is an evaporative cooler. If you want one, try an ad in the swap meet. Parts requests are not allowed in General Truck Talk.

"It's just a phase. He'll grow out of it." Mama, 1964

1956 Chevy 1/2-ton 3100
1953 Chevy 6100 "The Yard dog"
1954 GMC Suburban Now with a new proud owner.