As a backup direction indicator on my Legacy, which also has a 2-screen Chelton EFIS system, I'm using the 2-1/4" ADI from Tru-Trak.  It's a bit of an odd critter, but if you buy it with the GPS and backup battery options, it does give a heading (track, actually) indication that's completely independent of your plane's electrical system.  It also provides pitch and bank info.  Hard to find equivalent info from 2-1/4" instruments without spending a fortune.

Jim Cameron
Legacy N132X