Having just replaced the power steering fluid lines and clamps in my car, I finally discovered the hose dimensions.

The power steering hoses that go to the fluid reservoir are 5/8" inner diameter for the large one, and 7/16" inner diameter for the small one.

I was told by 2 mechanics that you should only uses rubber hoses that are made to hold oil / fuel based fluids, and not use coolant hoses. They apparently break down much easier than those meants for oil based ones. So I got rubber fuel lines from Lordco, and they fit fine.

Make sure to put the foam insulators back on the new hoses, since they are close to the exhaust manifold and protect the lines from heat.