Shape looks similar to the Coda 1000 that came on high end bikes circa 2000. Seems to me Cannondale made some red/white/blue bikes to honor those who responded to the 9/11 attacks. Seems likely that the saddle came from one of those bikes. Search around, perhaps you can find a pic. I don't think they were in the catalog. I have a Coda 1000 here if you want to compare details of the underneath parts.