Is there only gold medal caseback for Connise 168.018?

The watch I'm looking at has stainless steel caseback.

http://users.tpg.com.au/mondodec//Fullcalibresdata.V8.pdf

or

from Omega Official site

Constellation Gents' leather strap

Dimensions: Ø35 mm

Reference ST 168.0018
International collection 1967 - 1971
Movement
Type: Automatic chronometer certified
Caliber number: 564
Created in 1965
24 jewels
Central sweep-second hand
Case Stainless steel
Case back Screw-in
Dial With gold "index" hour markers and gold "stick" hands
Crystal Armoured hesalite
Bracelet Leather
Water resistance 30 meters

It's tones of homework to find out which belongs to which :-<