The spacers are just washers and you need to get the caliper centered on the disc.

There are no Porsche part numbers on the calipers but, what I believe, is a Brembo part numbers that I know nothing about.

One thing to consider, that I've seen in the past, is that the front and rear calipers can get mixed up. Their mounts are slightly different and if you bolt them up it will catch the disc as you described.