If you need 300 rwhp on a budget the best way to get there is going to be a supercharger or turbo kit.
Heads cam and intake on a stock short block is going to be way more work than it's worth and driveability will suffer especially since this seems to be your daily. You will also need supporting mods like full exhaust to get you to the number so the budget would really be stretched thin.
Nitrous will get you to the number at the track but around town will actually slow you down because you'll have to retard your timing to run a shot.
Supercharger will be far less work than heads cam and intake and can easily get you to 300rwhp and of you get a solid kit used can come on way under budget. You can then use the left over budget for gears and I would also recommend a shift kit and exhaust.
Turbo kit is the other option but will require a bit more work than the supercharger, most notably a tubular k Member and coilovers, but can also be had at a decent price both new and used. The other good thing about the turbo is it will work well with your stock gears.
Personally when I was a young lad in your shoes with a 95 GT Automatic I went with 4.10's, a shift kit and a 100 shot. The car was a lot of fun but I had always wished I just went with a Vortech or Procharger from the jump.
The above post is misleading OP!
A 2.3L supercharger alone will cost you $3,800 from Whipple. Add the better part of $1K for a manifold and another $750 for the pulley bridge. A Metco lower kit will cost you $400+, and a top pulley will cost you another $100. New injectors will cost you $600 + as much as 250 and possibly as little as $500. Fuel rails will cost you another $350 and don't forget the fuel pump hat. The fuel pump hat will set you back another $1,100. So far, we have spent $8,150 on the blower solution and we are far from finished. There is easily another $1,000 to $2,000 in plumbing and fuel system parts depending on what you choose.
The Turbo route is north of $10K, done right. If you are a good fabricator with access to a metals shop for fabrication, then potentially a small savings. Of all the mod paths you have to choose from, the Whipple path, by far will provide more torque at lower rpm and smoother acceleration than any other possible mod, and you will have no need to switch cams. We have many people on the site that have run low 9's and high 8's on stock cams.
A complete 150 shot Nitrous system from Nitrous Express will cost you $875 MSRP. Potentially less through distribution.
If what you said originally in your very first post is what you are looking for, then
The Answer is Nitrous! If you want to spend a lot of money, there are nearly unlimited ways to piss away virtually any amount of money you would like to. Pick your poison.