Hydraulic valves won't seal gas. Not the normal ones.
And a 5/2 hydraulic?? That's not a common one.
4/2 to control a double acting ram or reversable motor, that's more standard.

Most people use the Burkert 5404 or Chinese copy. That is a 2/2 valve that can withstand the pressure, and if overvolted, switch it dependably. To have a 3/2 equivalent, you'll need 2 of those.

, the benchmark for flippers since 2003, used 2 of those to feed the 100mm bore 180mm stroke ram, and 1 to release the pressure.