Take a look at this thread where various people have posted their Serotta CSi bikes and serial numbers. Lots of details on the evolution/changes over the life of the model.
Our illustrious admin Keith kicks it off with serial #272, and a quick scan makes me think you are in the 1995-6 range, since #808 (serials are sequential by model) was ordered late 1996 and delivered 1997 as noted in an early post.
https://forums.thepaceline.net/showt...serial+numbers
I think that your frame would have typically shipped with the 1" F1 carbon/steel steerer fork--with an all steel fork as an option--but there are more people with more expertise who should correct me if I'm wrong.
And I would have no hesitation in adding Robert's F1 to yours, should you wish to--it would be closer to original than what you have.
(And FWIW--my CSi is as good a steel frame as I have ever thrown a leg over, so enjoy that puppy!)