For the Bayard spring, contact Keith Kearcher in Bend, Oregon. Not inexpensive, and not done yet, but he said he could do it. He has a website. The 16 ga. Society was the source of this referral.
Happened on an interesting reference in an old book just yesterday which showed how to make one out of spring wire, wrapping it around the top screw. See Gunmithing: The Tricks of the Trade, JB Wood, 1982, pp. 181-182. I'll mail a copy of these pages if you'd like since it's probably not very available. It might work on a Bayard as the photo looks a lot like the sidelock of my Bayard, but there is a little notch at the end of the top of the spring that might mean some extra work.
Regarding rebluing of the Richmond. Yes, that seems logical given the character of the finish (which is pretty thin on the barrels), but its more of a uniform gray now, a process I'm not familiar with but I'm sure can by done by the skilled or by time and use.
