Sorry I can't find my link, but there were two makers with a kit advertising 500hp for someting crazy like $20k.   This might be one, 
http://www.roocksport.com/main/tuning_boxster.php  
Controlling detonation for hi boost will be very important for engine longevity.  Will probably require lower compression forged pistons.
Nothing wrong with wanting more power in the box.