I have been suspecting that my MAF seals are leaking little bit as MAF goes in too easily and after getting new OEM maf reading still are too low (~1.5g/l). So I started looking for other options as OEM 1 seal cost in Australia 122 AUD /~100 USD and I won't buy that. My work involves high pressure (+10000psi) applications so I use lot's of different seals and I noticed something what I can easily use.
It sits exactly into intake pipe first step (with light push). As seal has little lip at the top then this holds seal in place (sits on top of intake metal edge) when you are pushing MAF into it. MAF sits into seal good (not hard or too easy), when you look the pictures you see that this seal has another O-ring inside of it, this is called energizer, this will keep outer seal ring what goes against MAF always active/pushing against MAF to make air proof connection. I will glue these in with locktite 406 (difficult to bond materials) to keep them there when I'm pulling airbox off.
There is part number on top of the seal, this is basically measurement of the seal, you should be able to get these from any O-ring shop in States and they cost few dollars each.
I hope this is helpful.
