You might want to try asking over at http://www.telemarkeast.com/forums/
in the Gear Shop forum.
The skinniest metal edged skis I have are an older set of Waxless Atomic Raniers, 88/60/78, too wide for groomed tracks. I like them for touring and not too deep snow. They glide pretty well, I've gained some weight so the waxless pattern tends to drag a bit, but not horribly. I have 75 mm bindings on them and use the original Scarpa T3 plastic boot. Plenty of power for that ski.
I've heard many people gush over the Madshus Glittertind with a beefy NNN BC boot. They're 68 at the shovel, so they might be a little big for in track too.