I have two DAS recirculating protein skimmers available. They can be run either externally or in the sump. These are great skimmers and were manufactured for DAS by Deltec. Use all the same pumps and design. Both skimmers are 28" tall.
DAS EX-3 - rated for tanks up to 400g. Has an added gate valve and none of the return plumbing is glued so it can be made to fit your setup - $350 OBO
8" reaction chamber and comes with 3 needlewheel pumps installed
DAS EX-2 - rated for tanks up to 250g - $250 OBO
6" reaction chamber and comes with 2 needlewheel pumps