Mazda sell them, cost about $14. My local dealer initially thought they werent available seperately, and that the whole MAF housing had to be purchased. I remembered seeing mention on the forum by one of the West Aussie mob (sorry, name escapes me now) that the individual part WAS available.
As a stopgap I bought a pack of 4 o-rings from Bunnings for $2.60. The pack had 2 rings that were too small, and 2 rings that were ALMOST the correct size; oversize by about half a mm in diameter. I wasnt convinced they would seal properly so also bought the Mazda OE part. Just amazing tho that Mazda charges $14 for ONE.... Bunnings charge $2.60 for FOUR. C'est la vie.
Leon
Started out with nothing Still got most of it left