More power for cheap

I drive a 91 T-bird LX with a 5.0 V-8 under the hood. Im working on a limited budget (like 700 bucks at the very most). What can I do to crank a little more power out of this car for cheap? Ideally, i'm looking for a 50 hp increase (the stock engine runs at 200hp and 275ft/lbs). Is this kind of upgrade possible? If not, what is the most I can do with the stated budget?

Get a used GT40 or Cobra intake. The GT40 won't fit under a stock hood but you should be able to cut away some of the bracing in the hood and get it to fit. Get a 70mm MAF (making sure the MAF is calibrated to 19lb/hr for your stock injectors) and a 65mm TB. You may have some extra cash left over if you shop for the above parts. If you do, get either a cam or headers. I would go headers first because that is a huge restriction in the exhaust system. For the next round, get a cam and open up the rest of the exhaust, not just cat back, all of it.