Welcome! We have a good community here, with a plethora of knowledge.
First and foremost, most of us here applaud you for not swapping in a v8
. Second, 200hp is achievable with a 2.3, however its hard to do that and meet emissions testing standards (I think). A 200hp NA 2.3 requires three things. First a radical cam, second high rpm, third a well built head.
The cam is relative easy, they aren't cheap as a good high rpm/power roller cam costs around $400. This is the same price for roller cams of all profiles as they don't get much more expensive for levels.
The high rpm gets expensive too, but only because a good set of pistons/ring and bearings aren't cheap, plus good machine work. One of the easy ways to get power is to increase displacement which is done in these by increasing the stroke with a new crank. These cost about $2000 each.
The well built head will also cost a bit, but if you have it all done at once by a company like easlinger and bo-port can save you some money because they will sell you a built head with the cam and all valvetrain installed.
My suggestion is you check out your options as best you can before starting anything. Www.bo-port.com
and Welcome to Esslinger Engineering
are two excellent starting points.
Also race engineering sells an aftermarket cast iron head that performs nearly as good stock as a well ported ford head. I'm not sure their website address, but google them if interested.
Best of luck! If you want any more specifics don't hesitate to send me a private message, if I can't help ill point you in the right direction.
Edit* I can't forget, the first thing you should do is update the fuel system, a new 225lph pump is necessary, a tuner or standalone ecu is necessary (I suggest a quarterhorse by moates.net ), and injectors will need to be updated, for 200hp a set of 4 hole 30-35 lb/hr will work great.