The original importer of Mitsubishi in NZ had interests in oil companies, and had their own brand of fuel and oil, which later dissapeared in the late '80's. They were still involved in the oil industry, and were once known as ShellBPTodd. So then they used BP oils, and now it's Castrol. The old shop where I worked which is now shut down had old Europa and BP branded oil measures. Looking at the cartons that Mitsubishi sends the oil in, the MSL (Mitsubishi Synthesized Lubricant) comes from BP, and the DPF oil comes from Castrol. Probably the same place, just different names.
We get genuine Mitsubishi Japan trans oils, DiaQueen, and it comes in tins with Japanese writing, one of the few English words on the can is Nippon.