On one of these forums I saw a link to Distant Thunder Sights.
http://www.distantthunderbpcr.com/
I had a great talk with Jim who makes custom sights in addition to what he has on the website. He said he would make me a copy of the original Sharps Sporter Tang Sight for less than I can buy a quality existing tang sight. I have a Shiloh Sharps 1874 with a bull barrel (wt 16lbs) in 50-90. I wanted a close reproduction of the type rifle used in the hunts; straight shotgun stock, but I couldn't find a tang that looked like the originals that are in some of the pictures of buffalo rifles I've seen. I looked for a tang like the picture in Mike Venturino's book "Shooting Buffalo Guns of the Old West" (see picture) and in Frank Seller's book. I'm not worried about it being good for competition - I have another Sharps with an MVA buffalo soule for that. I thought maybe someone would be interested in having a sight much like the original Sharps Sporter. If so talk to Jim and he can make you one. Thank you to whoever posted the link to Distant Thunder Sights