My rear sight was made by CanadaTool & Speciality Co., New Glasgow, Nova Scotia, also called the last version of the Pilblad sight. Contact Barryj@localnet.com for an original rear sight. Since your rifle is no longer easily (or cheaply) restorable, I think your idea of a Williams sight is a good option. Barry will likely ask a series of seemingly inane questions but he is a total Ross geek and knows whereof he speaks. Let us know how it goes. Tom