it certainly has the S3 front panels and tail lights but its easy to fit the S3 bits onto a S2 or S1, nissan made the S2s for less than a year before they started building the S3, if yours is the S3 then you have the more expensive trans to rebuild but the same trans was used on the R32/R33 and is similar to the auto in my S1 r34 which gives you the option of using low K secondhand trans (i picked up a RB25 DE trans for under $250)
i dont mean to sound mean but whatever your budget is then look at doubling it~ if not more