Oyster Day/Date question

[jd_mass]

Hi, Jim from Massachusetts here and I am NOT a watch expert. I just found an "OYSTER PERPETUAL DAY/DATE" at the bottom of a box of trains and was wondering if someone could help. I am NOT planning on taking it apart to find S/N's or ID. (I'll take it somewhere professional for that), but if I post a few pics in a photobucket link do you think someone could help? I'd be very surprised if it is not a replica, but you never know. I won't post any links to pics unless someone is interested. Don't want to bore everyone as I'm sure you get requests like this alot.

Thanks (in advance),

Jim