Re: need info on 3 old handguns
I know of no source of parts for any of those guns. The springs would even be difficult to make if they are missing as the gunsmith has to first figure out what the spring looks like, then try to duplicate it. All are flat springs and would have to be ground and shaped to size then heat treated, a tricky process with a high failure rate.
I think I can say that having those springs made would cost far more than the value of the gun. Even the Colt New House in average condition runs only $600-700, and I can almost guarantee that having all its springs made by a competent gunsmith ($60+ an hour) would run a lot more than that. Only if the gun were like new in the box would it be worth fixing and an LNIB gun would probably not need its springs replaced. The same is true of the others, only more so, since they are of lower value.
By coincidence, I saw a Bentley (the revolver, not the pepperbox) for sale a week ago for $1400 in very nice shape, but it has been around a long time according to the dealer. My WAG on the value would be around $800.