IMHO you can get an approx. value of the watch if you search "Vintage cyma" on the bay and look for the closest looking watch to yours. The swiss industry churn out dress watches by the millions? every year back then..... if it is high in sentimental value, nothing is too much.
Maybe some other sifus might know more about this Cyma...
btw MWF store does offer service n crystal change... you might want to see them for an estimation....