I had built my own replica start switch for my cockpit project but was not too happy with the results. While browsing eBay the other day I happened upon a used Cessna switch (part no C292501-0101) for $5. Even though it had no key this was just too good of a deal to pass up. Shipping was only $5, so for $10 I had a real switch.
Last night I tore the switch down, cleaned it up and re-keyed the lock to fit the key from my scratch built switch. Apparently a C&K switch key, although shorter than the real thing, fits just fine. It is kind of hard to see in the pictures, but the switch was really dirty and the anti-oxidizer/grease inside had mostly solidified.
I used rubbing alcohol, some cotton swabs and an old toothbrush to clean everything up. The contacts were cleaned up with a bit of fine sandpaper. Now it looks almost as good as new.
Here are some pictures of the terminals.
They are labelled: R, L, LR, PR, GRD, BAT, and S. I am still in the process of documenting how the contacts work. It looks like I will need some kind of circuit to translate the various positions into some kind of meaningful input to FSX.