I have several sets of base '97-'99 brake calipers for sale. These calipers were in good working condition when removed. These were removed for brake upgrades to 996TT or Boxster S calipers. All are black in color, with the typical fading of a 60-100k mile caliper.
Front or rear pairs available for $350
I can help supply any kind of brake pads and/or sensors if desired.
Photos of a couple sets below. I have others stored away in boxes that I didn't want to dig out today...