i think the service center is correct that these parts are unavailable from d/d. i'm not sure if that's the problem though?

the best thing would be, imho, to send it to protime and see if it is able to be repaired. if you've already done that and they couldn't....maybe rgm? (link below) they have all the tools necessary to build parts from scratch. it will be costly i'm sure and the part won't be original heuer, but that may be as good as it gets.

on to your other questions, as far as i know the cal11 and 12 are very close. it is possible to grab a hamilton chronomatic (cheapest of the bunch and turn it into an organ donor. i've seen them running around $200.00usd-600.00usd or so. just make sure it's one that can't be salvaged as i'd hate to see a good one disappear.:) check on ebay every three days or so. there isn't a ton of them, but they do pop up from time to time. patience will pay off eventually. hope this helps?

j.h.