This is the hardest PAM to get parts for it seems -- I was in the same boat as you about 2 years ago. My solution was to buy one, then another and then yet another rep. I sent my gen down to Dallas, they came back and told me $2k and 120 days for the crown/tube repair (which included a mandatory movement servicing that I appreciated, but did not feel necessary) and I told them to sell it on consignment, which they did rather quickly and respectfully. After handling two Noob and one KW factory rep (and managing to do repairs on one Noob myself), I can definitively say that the parts are not interchangeable -- they are not even interchangeable between the Noob factory pieces surprisingly. And when I speak about "interchangeability," I'm speaking about crowns and tubes, tubes and cases and crown stems.
My advice is to take your gen dial, hands, movement, case back and crystal and put them in a rep case and hope like hell the rep crown & tube work. If not, you can shave down the stem or tube a tad (per a tutorial on this site) or fill the gap between the tube and case with black epoxy. Its not perfect, but a good lesson. Or you can pay the cash and wait for the repair. That's honestly easier, but I don't know our financial situation or patience level either haha. My issue was both money ($2k for a crown on a $9k watch seemed like $20k tires on a $50k car to me) and I'm notoriously impatient.
