Does your rifle have pre-64 style claw extractor on it or is it the push fed style?
I am not exactly sure, but I don't think Winchester made a stainless featherweight until the late 80's or early 90's.
Did you put your serial number in at this site:
Question #296, What year was my Winchester manufactured? (Serial Number Reference) -- Winchester Repeating Arms
I have 2 featherweights, and like them both very much. One is a push fed and the other is a FN Classic with the pre-64 big claw extractor. The FN is a stainless.