Emerald has a number of options, as others have pointed out. Here are a couple of examples:
The X20-12 has a 1 15/16" nut, and 2 1/2" spacing at the bridge - that would be a very straightforward starting point for a 6-string variant, I'd think, and probably the most economical.
The X20 Nylon is 1 7/8" at the nut, and 2 1/4" at the bridge, so again, could be a good start, but significantly more expensive.
And if you really want to go nuts, start with an X20-7, 2" at the nut, 2 5/8" at the bridge, have them make it as a 6-string and go dancing on those fan frets
