Looking at a 1967 230S in excellent shape. Beautiful car with 90K miles, second owner. No rust and interior perfect. Transmission fluid is low and the owner is trying to figure out what he can use. Is Dextron II OK to use?

What is this car worth, he wants $4K. Other than the fluid low in the transmission I could find nothing wrong with the car, looks like it came off the showroom floor. even has factory air that works, has power steering and brakes.

Thanks