Ask them to try SAAB numbers, they are the same seals but different part numbers. My Opel/SAAB dealer got me them that way.
It should be SAAB #9129999
https://www.skandix.de/en/spare-parts/cooling-system/thermostat/gasket-thermostat-housing/1017454/
How are things going in your part of the world Jan. I hear that Sweden are trying a different approach to the rest of Europe regarding the virus. Stay safe.
Yes we did it differently, they get a lot of flak for this approach and we will see if it is good. Biggest problem for us is the total lack of resources. During the cold war we had 60 military field hospitals, now we only have two. All medical supplies are in the "Just-In-Time" supply chains and much is imported so that supply chain is more or less broken.
Business going belly up, but that's the same everywhere.
Myself I live out in the country side and are more or less always self isolated, working from home anyway, so for me it isn't much difference. Wife is retired and we live a relaxed life normally. Going for groceries you have to be more careful of course.