Loop,
did you really join the ZIC group? Took me couple of days to get there, and mind you that this is an e-mail based group that simply spreads your mail to all members, so it may take quite a while until the right member (the person with the information you need) has read your mail and found the time to answer.
Perhaps Mike Elek, Mike Kovacs or Stephen Gandy are around here or in the collectors group and can give you a hand on that one.
For the time being, the Carl Zeiss Jena Sonnar 5 cm f:2 No. 1862046 is the only pre-war (1936) part of your equipment according to
http://home.sprynet.com/~stspring/Zeiss Ikon.html
Second, have a look at your camera bodies for a hint. Production years were 1951 to 1960, starting with black numbers on the speed dial, later switching to coloured numbers (and an improved flash sync), often these differences are being referred to as "black dial" and "color dial".
If all fails and you are willing to spend your money on a definite solution, you can purchase Hartmut Thiele's serial number book on post-war Carl Zeiss Production (with Opton indicating that your f:1,5 Sonnar is from OPTische werke OberkocheN, W Germany):
http://www.lindemanns.de/4DCGI/2073197993/TitelAnzeige/351153
For the camera bodies, it is possible to drop Zeiss Germany a mail. As far as I know, they are in keeping of the records for the bodies an can possibly tell you the year of production (which they have been said to do earlier in one thread). They offer this service explicitely:
http://www.zeiss.de/C12567A10053133C/Inhalt-Frame/C9F1B3FB3CD2C2B941256A72004AEA3C
Just place the tag in the first box "Anfragen zu ...historischen Produkten" and put down your questions.
Wishing you success!
Jesko
