DG4V-3(S) Series Danfoss / Eaton Vickers Spare Part Spool Kit

At 4500 psi you're above the 3000 psi threshold where a steel subplate or manifold becomes required. Cast iron or aluminum subplates aren't rated for that range with this valve. If your existing subplate is already steel, you're good to go. If not, that's something to sort out before putting this into service.

The product description notes it can handle water-based fluids, but only in a temperature range of +50°F to 129°F. Mineral oil has a wider range, from -4°F to 158°F.