I'm looking into purchasing a copy lens to use as a telephoto lens on my 4x5 because of the cheaper cost. Does anyone know of a good resource for information on these lenses (specifically in the 240-360mm range)?

I know the lens will be lacking a shutter, so for the time being I'll just cover the lens and shoot for 1 second plus exposures. But when I decide to have a shutter put on it, what's the general range for this time of work?