Best I can find is about 17% of GDP in Norway is from Oil and Gas. While that per capita number is high, it's not Saudi Arabia levels.
Per capita doesn't mean % of GDP though. It means relative to the population.
Norway exports like $50B / yr of petroleum (and another $120B of natural gas). Saudi Arabia exports like $170B / yr of petroleum.
Saudi Arabia population is like 7x larger, so per Capita oil and gas is larger in Norway even if you subtract out all the natural gas.
There, now your GDP is just 50% oil.
[1]: https://www.regjeringen.no/no/tema/okonomi-og-budsjett/norsk...
For sure, it's a huge part of Norway and shouldn't be overlooked, but it's specious to compare it directly to a country like Saudi Arabia.