Accumulator Charge Valve

I was curious to as if anyone has more experience when it comes to charging brake accumulators. Ive got a Case 621F with a bad front brake accumulator bad so im going to replace both. About the charging valve- is there any specifics about the so called special charging valve regulator I need? the one its calling for to use is $800, ive already have the charging adapter that you screw on to the accumulator(found it in my old service truck-lucky me) thanks for any input

Accumulator Charge Valve