It would depend on who they sourced it from. Trucks didn't get an A/C option until '59 from GM, anything earlier would almost have to either be dealer fabricated or aftermarket. That said, the '59 factory A/C for trucks used a Harrison compressor, most likely the A6, which is arguably the best compressor ever made. Aftermarket systems would possibly used a York 2 cylinder.
Good luck in finding one, A/C on a truck was rare. You might look for a passenger car version, and adapt it.
