Norman with a 32 PBIC it should be easier to find an air cleaner, try James Geddes, he has broken a couple of cars. Chris at Club spares got a lot of parts from Andy Burnet so it’s worth giving him a call as well. Failing that to get you on the road CAS do a ‘Universal’ one https://www.cas-shop.com/en/product/universal-airfilter-o52/ OK doesn’t look original but would get you going.
David Faulkner