I’d like to match this dial/movement combo with the proper case reference. The dial and movement diameter measure about 28.43 mm and thus appear too small for chronometer case reference 8355 which is 37mm diameter. I’d appreciate suggestions on a possible match. Being that the markers/hands are gilt, does this have bearing on the type of case metal (ie stainless steel vs gold or gold capped)?
On your first question, I think all of the dials marked “Ultra Chron Chronometer” would be compatible with the 83XX series of cases. Inside this post are pictures of several references: https://omegaforums.net/threads/longines-vintage-catalogs.19824/ It looks to me as if there are really only two styles of cases for the chronometers, either tonneau or "C". I think the gold dial furniture would go with both gold plated and solid gold cases, but not with steel. I own a Ref. 8352 and Longines told me that the dials on those watches are not solid gold, although mine certainly looks the part. Hope this helps, gatorcpa