A pod filter will pass pits, if its fixed to the body by a bracket of some sort (any sort, as long as its not flopping about).

I would think the rubber tube/pipe for the BOV could be sourced anywhere? Bunnings? Repco? Clark Rubber (just throwing ideas about)

With your current wheels, are you worried about the size and width, or are the tyres cactus? What's on there at the moment?