It's just a few psi, 2-4. Volume is critical but too much pressure isn't good for Weber's. Pierce manifold has good info and a few pumps to choose from.
Fuel pumps for similar engines of this period: The 365 GT4 BB workshop manual (English translation) says 2.5 to 3.5 meters H2O for the Corona fuel pump, i.e. 3.56 psi to 4.98 psi, the flow rate is 100 liters per hour, i.e. 26.4 US gallons per hour. The 365GTC/4 workshop manual says 0.25 to 0.30 kg/cm2 for the fuel pump (Bendix 476087), i.e. 3.56psi to 4.27psi. The flow rate is not specified, but most likely similar to that of the Corona.