OK - Now that I own a Disco II and the Defender is on the way out. All of those, when I build my own Defender dreams - well they are on hold. I ended up with two snorkels (long story, but did involve some snot-nosed kids vandalizing my rig).
I have most of the parts for a Mantec snorkel - the bell shaped pre-cleaner (if that's what you call it), is missing (well, it flew off on I-10). The plate that mounts it to the wing is partly deformed. I think it would be pretty cheap to fix. A pre-cleaner would be fairly cheap as well, and certainly more effective.
Make me an offer, I know these things are $499 new. BTW - the paint and everything is perfect (except at the bent edge).