Yes, lately it is not uncommon to see that they are looking for crystals, and, first of all, for 1950 chronographs.
All the latter, resolved their issue with the WSO.
If the 297 problem can be solved with the WSO, it will be very interesting to see the final appearance.
If I had known, I would have written about it right away.
I think it makes sense to ask Prof, or Natas, they may be able to advise something else, but I'm not sure I've seen anyone recently find a cheaper crystal of comparable quality, if we talk about a dome crystal.