k... with that budget, you need to put the SOHC cam together, and sell it. you won't make the power you want to make with it and you'll end up hating yourself later for it.
Buy a DOHC.
eliminate all of the emissions and anything you don't need off of the manifold.
google s13 emissions removal. you should find some good walk throughs
With the manifold off, get yourself a dremel, with that extention peice and some grinding bits. You'll want to grind out all of the bumps and what not in the inside of the manifold.
google DIY port and polish s13 manifold. There is a good write up by a guy that has the Username bigvinnie. Can't remember what forum he is on, but its out there.
Meanwhile, carefully pull apart the block.
Get your hands on some SOHC pistons. a lot of the places that sell rebuild kits, will put the SOHC pistons in your kit if you call and tell them that's what you want when you order it.
(normally, I would tell you to tear it all the way down and do a totall rebuild, but that isn't in your budget, so I highly suggest getting this all together, then start saving for a "real" rebuild kit with things like oil pump and all that fun stuff)
Get the SOHC pistons installed with new rings and bearings and all that fun.
Meanwhile, I would send the head off to at least get decked. (Normally, I would suggest getting it totally worked over, hot tanks, valve seals, new valves and springs, 3 angle valve job etc, but that is again, out of your budget. so once you get the cash saved up for a real nice rebuild kit, save up for an extra head and get all of the work done to it.)
The SOHC pistons should get you 11.1to1. (I think, I honestly can't remeber if it is lower than that or not)
Getting the head decked should bump that up to between 11.3 and 11.5 to 1.
depending on how much the machine shop charges, you should be between 600 and 800 bucks. depends on how much your little rebuild kit is and how much the machine shop charges.
So now you have a nice smoothed out intake manifold, bolted up to a head with a fresh headgasket and new single cam pistons. At this point, I would suggest getting it broken in. you'll have to run premium and you'll have to play with your timing to keep from detonating.
Then relocate your battery to the trunk to make way for a custom intake.
You can either choose to buy an intake and make it work, or you can get creative and make something that will work just as well.
If you want to pinch your pennies, you can make an intake using dryer vent piping. The hard metal stuff that you rotate each section to make a bend. bend it around to get it to point in the right direction, then use a little straight piece to put the air filter where you want it behind the headlight. Use rubber cement or something to seal it up and make it air tight. Then maybe spray it with rubberized undercoating for good measure. You'll have to hit up goodyear rubber to get a coupler made that is the right size and what not for your new intake. It isn't perfect, but it will get the job done better than stock and much cheaper than aftermarket
Maybe even take it a step further and build a little insulated air box our of that flame retardant insulation board and A/C duct tape and use one of the slinky style dryer vents to vent air from the little air vent below the head light up to the air filter.
again, not awesome, but it gets the job done.
Then get yourself some off-the-shelf header. A total custom one would be best, but again, out of the price range. Anything is better than stock really.
Then go crazy with heat wrap. Wrap the header really well. Its cool to keep under hood temps down, but more importantly, the hotter the exhaust gas is, the faster it will move and the faster it moves, the more vacuum (or Scavenging effect) it has and therefore, the more power you'll make.
Hit up the junkyard and get some exhaust piping off of things like pick up trucks and such. You just want the pipe to be a bit bigger than stock. Pick up trucks usually have the pieces that you need. You just want to piece together a straight pipe exhaust to go from the header out the rear of the car with a few bends as possible.
If you want to be nice about the whole volume thing, then try gutting out a stock muffler or something off of another car at the junkyard. Or really splurge and get something cheap from the parts store. If it has that annoying ricer honda sound to it, try wrapping the muffler and tip up with some heat wrap. Should help. Think about it like wrapping a towel around the bell of a trumpet. It really muffles the sound out because it keeps the bell from vibrating.
Use a screw driver and hammer and dent in the bottom of the fuel pressure regulator. That'll up your fuel pressure some. Doesn't need to be much. Just a little bump. Saves you from having to buy a walboro or something.
Get an old SAFC and borrow a buddy's wideband o2 sensor and even your tune out because at this point, you'll be running really rich.
get your hands on a MSD Blaster coil... they sell them at the parts stores. And do the relay mod so you're getting power straight from the battery/alternator instead of all through the harness. I'd say do the same thing for your fuel pump.

all that should put you right at the 200 hp mark and should make for a very rev happy engine.

there is more you can do, but it all costs more money.