Your pump appears to be a Williams 4 piston model and the hoist is definately low pressure. Tie rod cylinders don't take a lot of pressure but you pump will develope up to 3000 psi. There is a relief valve on the pump that should not be set above 1000-1200 psi. The pump will never exceed what is required to make the piston move but with a lot of resistance (work) for it to overcome your pump could blow it to pieces so it is a matter of safety that the relief valve be set correctly. It may be either adjustable or non-adjustable.
Your directional valve appears to be a correct 3 way valve. Check your hoses too for condition and pressure type.
Incidentally, those two "solid rams going back to the bed" are called the lift arms. When hoisting and in the full up position they along with the pivot arms form a triangle which provides the mechanical advantage. It is a quite old hoist so be careful when using it, it may have stress cracks, etc.
