Discovered a 1970's Longines Ultra Chron

[nfld]

Hi all just found or re-discovered two watches this past weekend at my in-laws. One was a 1950's Tudor Prince 34, which I posted under the Rolex Vintage section, and the 2nd watch is this Longines Ultra Chron, see attached pics. Can anyone give me their thoughts on this watch, its cost at the time, it's replacement value, how to get it serviced..etc. My father in-law still has the original box and purchase slip for this watch, he bought it over 43 years ago, May 12th, 1972. The watch is a little weathered as my father in-law is a farmer and thus wore this watch while planting/plowing..etc

Thank you for your replies in advance.

[FTX I]

You can search for a watchmaker in your area to get it serviced. Very nice watch. Congrats.

[Franks07]

I love my Longines Ultra-Chron Automatic Date. The cal. 431 movement runs at an incredible 36,000 VPH (thus the outstanding accuracy when properly maintained). This is a very specialized "hi Beat) movement that requires regular lubrication with special lubricants designed to stay in place and protect at such a high VPH rate.
Very special and currently undervalued vintage mechanical watch IMHO.