Since I'm no longer tracking my '99 Boxster, I have some gently used (1 DE weekend, 2 total days) Hawk Blue front and rear pads for sale. New, they're going for about $290 for the set these days, asking $150+ shipping. There is about 3/8" (9mm) pad remaining on them.
These pads will definitely fit a '97-'99 2.5L Boxster. I can't confirm they will fit any other model years. Please check for your own situation.