Advice on refurbishing an old calabash gourd pipe

I have recently bought a fixer upper calabash gourd and want to know the best way to getting it fixed up. There is a small crack on the rim, the stem is broken off in the ferrule and I want to put an actual meer bowl on it (it came with a chipped porcelain one). I was thinking of trying my hand at turning a new ferrule and stem for it and wondering what might be a good one. I saw some acrylic pen blanks that seemed like that might be an idea for the ferrule, other ones were maybe a briar ferrule or fossilized Mammoth tusk (although I am kind of wary because that stuff is expensive). So I guess my questions are:
1) Where would be a good place to pick up a meer bowl for it?
2) What would you guys suggest for the ferrule?
3) What is the best way to clean out all of the old junk?
4) Any general advice for turning things on a lathe? (I have never done it before)

I just replaced the meer bowl insert in my calabash with one from an Ebay seller in Turkey. I can't recommend his inserts enough. Here's a thread that I posted with some pictures.

Maybe you could sand down the rim a little to reduce the crack before fitting your meer insert? Do you have pictures of what you're working with?