It's a long time ago but from what I remember the 330 Puma had the single oil pump on the back of the gearbox driven by No1 accessory drive. The shaft was hollow so that with a suitable bottom plate and drag damper oil reservoir a shaft could be extended above the rotor head for optical sighting equipment etc. Your photogragh also shows the No1 engine drive disconnect system where you could run No1 engine with the main rotor stationary but with operational No1 Alt and Hyd1 and drive it around on its own powered tracked undercarriage.
The early (up to the E model) did not have an oil pressure guage so the present problems would not happen. There was just a temperature guage and a MGP(P) on the SWP. A way of checking it was to pull up to about 80 degrees nose up; this would cause all the gearbox oil to flow to the rear of the gearbox, uncover the oil pump inlet followed by the pressure light.
In 1971 the Puma's max was 6,400 Kilos. I last flew them at 9,200.