Check on Classic Rendezvous ( http://www.classicrendezvous.com/main.htm ) they
have photos of windsors.
As far as I recall they (windsor) were the only ones who did the fake cinelli's.
Cinelli wasn't all that meticulous a framebuilder (got my nomex on), I've heard
sloppy be used in conjunction with a number of classic italian bikes.
Serial number? that may help.
The CR list (instructions on posting at Classic Rendezvous) might be a good place
to ask about the bike. If they don't know, no one will.

Marty