I'm 5'9" with a Grand Prix from the same era, and it's a 21". The men's frame is probably a 23". Unless you have really long legs (in relation to your torso), then it's not going to fit you. I've bought tons of lugged steel vintage bikes here in NYC, and the going rate for a decent one with aluminum wheels starts at $100. I think that the Bay Area's going to be similar, though maybe a bit cheaper. In your price range, you'll be able to get something really decent there, I'd expect. Also might want to try garage sales and thrift stores, especially in areas like Orinda, Walnut Creek and other affluent 'burbs.

If you find something nice with steel wheels, then it should cost you less than $100 ($50-$75.) So those Raleighs are right on the money. I bought mine for $50, and changed out the wheels. Actually converted it to fixed gear (no deraillers), and it's really nice and light. Only spend time on this because those are some of the most common vintage bikes out there, and because of that, they tend to garner lower prices.

If you're patient and diligent (check, re-check CL every few hours--once you start, it becomes second-nature, right after e-mail), then you will find some very nice deals. You just have to be very quick about responding to new posts.

When looking at pics online, even if the person doesn't know how to measure the bike, you can roughly eyeball by looking at the headtube (where the stem enters and the fork emerges.) For someone in your size range, this should be close to just a meeting point for the two other tubes, with no more than 2-3" in length.

I recommend going and checking out bikes that may not fit but look nice, just to get an idea of what to look at.

Thing with vintage bikes is that you often buy them and have to spend money on getting them back up to snuff. That's okay, but you should be able to calculate that a bit. Learn to measure the chain length, look at the trueness of the wheels (very important--I've been screwed when I missed this) and--VERY important, VERY IMPORTANT: make sure that the seatpost is not stuck in the seattube! If it is, then you either should walk away, or plan on getting someone to help you and spending some dough. Haggle the price waaay down. But really, in your position, unless you've found some amazing gem, walk away. Stuck seatposts just aren't worth the hassle, esp. if you're a newbie.

But a new chain will cost you 15-20 bucks, and wheels may be so messed up that they have to be replaced. Wheels are expensive to replace. And if you need new tires, that will probably cost you minimum 20 bucks.

There's tons more we could each share, but some of this will just come with experience. Do not let people tell you that it can't be done, though. It makes for worthwhile learning.