There are undoubtedly TONS of bicycle coops in the bay area. Find one, ride the bike there, and say "I need some easier gears." They'll likely have what you will need along with the knowledge you need to put it together.

I'd really recommend against trying to get nice modern parts to work on this bike. Generally mixing new stuff with old(er) stuff is a recipe in frustration. Also, if you ever did get a new bike the stuff you put on the old bike likely wouldn't be compatible since the clamp diameter of the front derailleur would be different, among other things. Old stuff is perfectly functional and just as nice as the new stuff you'd be buying anyway.

I'd really recommend going to your local bike coop and asking them for help.