I think you will wind up making your own template. Barb does some signs using a method of printing out a reversed outline, then using (I think) peppermint oil to transfer the outline to a piece of 3/4 MDF. Then you use a jig saw to cut out the shape, sand and smooth it out and use that to rout out the shape.
A detailed outline will be a problem because the square corners of the state will have to be hand cut, and you will have to simplify the jagged southern border.
Another alternative is to use a router plane (pix), with the inlay kit (pix) to cut the recess for the inlay. If this is a one off, that might be simpler, and if you like inlay work and expect to do more the Veritas plane shown is something you will really enjoy using. You can still use the router to hog out the middle and the plane to create the detailed borders. To be honest, I've not used my plane a lot, mainly to flatten the bottom of quick and dirty and odd sized dados and grooves.
You could start by routing out most of the middle areas, then set the router plane to the depth of the routed areas, then cut out the outline area and hand plane up to those borders. Note the cutter on the the inlay kit. You have a lot of control with the router plane for the fine work you'll have to do somehow. I also dropped in a pix of a miniature router plane, but it doesn't have an inlay cutter kit option.
As always, the pix are out of order. First is the miniature plane, then the full sized Veritas router plane with the bottom flattening cutters (wide to narrow), and finally the inlay kit, which is set up to do double cuts for things like vines. You can also use the single cutter. Setting depth will be easy, set the router bit depth, clear out a small area, then set the depth of the cutter set or chisel for an exact match.
For a 6 inch wide inlay, you'll surely need a very wide base on your router so it doesn't tip.
Hope this helps
