The funniest AW11 story for a while:
I mentioned earlier how I tried to order some supercharger oil from Toyota, because the oil level was full 2mm above the low marker.
I contacted Toyota Tsusho Nordic and gave both part numbers for supercharger oil I had at hand. Both part numbers redirected to 5W-40 oil inside the Toyota EPC, which I thought was wrong. The parts guy at Toyota came up with the same conclusion and told me that he would contact someone at somewhere about this "might-be" error.
I waited for two weeks frustrated, after the guy from Toyota called me and told, that he got a recommendation from TTE (Toyota Team Europe) to use 75W-90 gear oil, because the original supercharger oil was not available anymore. I was both disappointed and happy. Now there was need to drain the old oil from the supercharger and I had no tools to fill up afterwards. The good part was the price. Only 22 euros for one liter, compared to 40-something euros for 50ml of original oil.
I ordered the oil without any hesitation.
Now it's official. This is the recommendation for alternate supercharger oil from TTE. Toyota part number for the oil is 08885-80606.
Why to trust TTE? Well, they have built Toyota WRC rally championship cars for ages. They built and raced the only Toyota GT1 car and now they are in charge of building the Toyota F1 car. They still have a selection of superchargers for different Toyota models, so I do believe that they know what they are doing.
(Edit: TTE is now known as Toyota Motorsports GmbH)
I had these part numbers for the original oil:
Thanks! Excellent service from Toyota.