Do you have any thrift stores in your area? Some of the ones around here have a wall of AC adapters, and it is almost always possible to find one that will work with an NES since 9V is pretty common, and it takes the most common barrel (connector/plug) size. As has been said, the NES doesn't care if it is AC or DC output from the adapter, and 1A isn't too hard to find, either. And a cable with RCA connections shouldn't be hard to find. Based on what I have laying around, I'd be shocked if there's anyone that DOESN'T have one in their house. Okay, I'm exaggerating, but still, it is something that someone you know and see daily of has extras of. In the meantime, you can use that RF adapter.
That's a nice bunch of games! Congrats again! Now get cracking on that mug set for the guy.
edit: whoops, cross post. Well, if thrift stores won't work, then I'd still say you've done pretty well.