Well, nice condition one`s can run up to $40+ each and it seems that everyone needs them! (they are almost as expensive as Summarit caps, which are also $50 to $70 each)
I have a really nice Summicron cap on my 1943/45 issued "coated" Summitar that was one it when I bought it, while it`s not original, the Summicron deep cap it holds on better, and I`m honestly not here for a beauty contest, I`m here to shoot with my old cameras and lenses, so if you can stand not having an original cap, but still buying a Leica one and one that WORKS BETTER than the original equipment cap, I say buy a Summicron cap.
I think that company selling on evilbay even makes them repro now as well....
Tom