Hello, Wondering What kind of Model the snipers van is from tf2

I know its a 1965 land rover, not sure what kind though or if it is a long base or a short base truck, Wondering how much it would cost to make something like this, and any problems that can be circumvented.

I know Mileage in cars from the 1960s is not the greatest, is there any way to improve this significantly especially if carrying a heavy load like a camper?

I really dont want to end up with a car that only gets like 8 miles per gallon