this may or may not work.. years ago i needed a filter for something on an old ford, cant remmber, but anyway.. the parts place did not have one for my particular model, but did for another one.. the one they had was bigger, the same fabric(mesh).. i got it and just put the one one by it and cut to size... if you need to filter the fumes(maybe the oil fumes) you can cut some mesh and poke it down the hose and this will filter the oil from coming up(well most of it and probably do a pretty good job)...
hope this helps.
just make sure you dont plug up the hole solid, let enough air flow to the PCV....