What octain should the fuel be for my 1995 impreza wrx jap import being run on shell v power at the minuit also how can you test the oil pump?

Unless the engine has been modified to raise the compression level from the original manufacturer specifications, "regular" is all you need, plus it's better to use "fresh" fuel that hasn't been sitting in the ground forever. Most stations sell a lot more regular fuel, so to protect injectors, buy what sells the most. Regarding the oil pump, if you have low oil pressure, change to a higher viscosity oil before you do anything expensive. The oil viscosity number is marked on the bottle/can and looks something like "5W15" or "10W30". Whatever numbers you HAVE been using in the past, try oil with a higher number then see what the oil pressure does. If it goes up, the oil pump is fine and it's just worn bearings. As long as you can keep the oil pressure up, the bearings aren't that bad, so don't get too worried.