Mac Shops (Haynes McDaniel) made several styles of aluminum extrusions with windows punched for various types of cars as per prototype.
You could also try OK streamliners in NY state (I believe.) He produces aluminum extrusions of various types and will punch windows as desired.
There is another fellow doing various style car kits in plastic, but I can't recall who it is at the moment. I'll try to find his info.
I believe the cars you want to model have corrugation below the windows only, don't they?