Hi Jimbo,
Grey Oil pump gears are scarce, we did have a couple of sets at last year's VIC Club Auction that went for close to $100 each.
A guy from the FB-EK Club in NSW has tried retro fitting red motor oil pump gears into a grey pump - it is possible with minor machining....
One of the guys in the VIC & Wangaratta Clubs (he drives a yellow FE Panel Van
) is currently attempting this modification but is yet to complete a unit. He has done the machining and yes, the gears can be installed by machining down the shafts. He is investigating the relief valves and will then bench test to check pressures etc. When he has done the testing he will advise how it is done.
Let me know by PM if you want a copy of the "instruction" on how to modify the oil pump to suit the red motor gears if you want to try it yourself.
Cheers,
Trevor_B