I've told this story before, but I'll tell it again since we're talking filters.
For the cars were I couldn't find an aftermarket filter and didn't want to pay for an OEM filter (some of the prices used to be bonkers), I buy the best furnace filter I could and cut it up into matching size for my cabin filter. I'd get 4-6 cabin filters from one furnace filter.
Easy DIY if you're ever in a pinch.