ISO 48cm (East Hill size ) road frame (or a complete bike)

My sister has decided that she doesn't like riding her cruiser (looks like a mid-'70s Raleigh, and about 40 pounds) around anymore and wants something lighter and faster - so I decided to build one up for her birthday. I'd prefer if it took 700s just for ease of finding tubes and tires. She's about 5'2 with short legs, I haven't been able to put her on a bike to confirm but she said that she measured herself and put it into an online calculator and it told her a 48.

Budget is something of an issue, and I'm not looking for a Colnago. If I could get something that isn't hi-ten and preferably not old French (my stock of French threaded/sized parts is low), I'd be happy.

I'm in NYC without a car, although I can get on Metro-North/NJ Transit/rent a Zipcar if it comes to it.


ALSO:

In need of two 1" threaded headsets - I'd dearly love Dura-Ace HP-7400s, mine is decent on the outside but pitted to hell. Other, interesting old Japanese headsets a possibility too. Have one of those damn 600 ones with the scalloped nut that's impossible to find the tool for, so not one of those
Have cash and a small stash of parts for tradin'.