Yes, the S front sway bar will fit the Base model. The front S sway is 21% stiffer than the Base stock sway. The M030 is 9% stiffer.
The 996 GT-3 sway bar in the front and the Tarett 986 sway bar in the rear are both adjustable. As you can see from the chart below, the front GT-3 sway is 66% to 225% stiffer than the Base sway (depending on the setting).
Do a search and/or ask for feedback from the Forum to find which sway bar will meet your needs best.