The one I used came from a Dodge Intrepid (I think), but any of them will be similar. I used a piece off of one end, trimmed to about one full coil past where they tighten up. It is the perfect length and tension for a light ejector spring, and is easy to assemble into the bolt.
I got the kit in from Brownell's, but ended up going back to the COP spring for the ejector because it works much better than the long spring that came in the kit.
As always, YMMV.
