Airnutz-
A couple of things that were in the post that got eaten...
On the C2s- there is one in Oregon that flies, one project that is slowly being rebuilt to fly, owned by Greg Herrick, and one that might just be paperwork owned by Tony Morozowsky. The Morozowsky example, if it exists, would be interesting as it is a one-off where Spartan experimented with installing a Szekely 45 hp engine instead of the Jacobs 60 hp engine. Both were three cylinders. Can you imagine? So as I said, 2, maybe 3. The one in Tulsa is George Goodhead's, and when he restored it he had parts of 3, data plates for 2, only could satisfy the FAA on an ownership trail for 1.
On the NP-1... George was given permission by Spartan to go clean out the attics at the factory before they sold it. From what I understand, he found the C2 plans, the NP-1 plans, and at least some sheets from the C3 set. The only ones that I know are available to the public are the NP-1 plans. The C2 and C3 plans are long-lost. The museum here in Tulsa has a few isolated sheets from the C2 and NP-1 sets that are the original pencil-drawn sheets, including the instrument panel layout for the NP-1 and (I think) a tail assembly for the C2.
And yes, it was very important to Tulsa at the time. W.G. Skelly marketed that thing all over the place, got told no by the Army, and finally got a small yes from the Navy. According to a variety of souces, the workmanship was pretty shoddy- one of the reasons J. Paul Getty went to Tulsa during the war was because he was asked by the Navy to go sort out the problems with NP-1 construction at Spartan. But it was a big deal- Spartan's first military contract (at least with the US military). Getty working things out led to a lot of contracts for parts production, which meant a lot of jobs in this Dust Bowl state at the end of the Depression.
I would love to rebuild the remnants of the other NP-1. It just takes money, right? And yes, I think the only person who would want to do that would either be a Spartan nut or someone needing all three primary biplane trainers used by the Navy. Or, just maybe, the NMNA- they are missing one as well...

You're welcome on the photos. Any more of the NP-1 you need, just ask. I'm there all the time. I am probably going to pull a bunch of the panels off of the airplane Wednesday to let it be displayed a little bare for a while- let people see how they were really constructed.
kevin