I have been bitten by the IWC bug lately and first collected a YG DaVinci perpetual calendar. Then I added 2 Portugieser watches, including a beautiful Yacht Club SS/RG combi. I was happy with my choice of IWC watches, but felt that no IWC collection woul...
You must have the original 2.5Hz model. As to the crown, IWC replaced them during service due to a dispute they had at one point. You can now request a fish crown if you send your watch for service to IWC. watchesbysjx.com
In fact, seeing yours is what started me on my search for a pilot watch, although I ended up with a different one. I am glad to be a member of the IWC pilot-watch club.
Mine is an early 5002 purchased in 2003 as soon as they became available in the US. I just went and looked at older pictures from various years and didn't see any patina. So, either mine was not early enough or the dial may have been changed during a serv...