If the bike is truly a 69 racer, then the wheel you just got from the seller is likely the original to the bike, as denoted by the "69". The hub you bought on the bike was made in 1966, but it just could have easily been used in 1969 if Schwinn was sitting on a ton of leftovers...anyhow...

You can easily change the cog on the hub driver out to something easier for you. Cheap and easy.

Check out this for some AW info. I can't believe you had trouble finding stuff on it, the AW is the most common SA hub EVER

http://sheldonbrown.com/sturmey-archer.html