Good for you Kenny!
If you find that you're short one of the Winchester Winchoke "invisible" Choke Tubes they are easily obtainable from a number of sources. Just make sure you order the flush fitting "3rd Style". In addition to the originally furnished choke tubes I mentioned above, Cyl and XF are also available, which I purchased through Chris Showler of Double Eagle Trading Co. for my SCC.
http://doublegunshop.com/showler.htm
Scroll down to the 2nd to last paragraph.
When you get your new-to-you SCC, please post some pics and measure the chambers and report back. It'll probably be roll stamped 12 GAUGE 2 3/4" on the left barrel, but there's a strong possibility that they'll actually measure 3".