Rebuilt calipers from PMB will run about $150 each all said and done once you return the cores.

I ended up ordering Porsche calipers for the rear only at this time from our host. About $250 each. As noted, I've seen several options for excellent looking rebuilt calipers at about $300 per set, but these usually require you to pay a core charge and return your old ones. I wanted to keep my old ones and make a winter project of trying to rebuild them. Given the number of "challenges" I've faced when trying to do anything as a first time Porsche owner, I didn't want the driveability of the car to depend on my ability to get this done. Hopefully at the end of the day I'll end up with a good rebuilt set.

As suggested, the issue with no pedal was just air. Firmed right back up with a quick bleed. Now just waiting on my new calipers. Thanks all for the tips.