REMINGTON 870 20 GAUGE CAMO FOR DUMMIES

I would like to locate a barrel that is for just a wingmaster only? What length will get me to original and they are there extended barrels offered? To who must I switch Other than ebay?I have witnessed a LOT of Standard 20s used in Skeet and no difficulties. The cracked 1100 I didn't get to look at had a hole drilled and was continue to trucking.