Short answer, you won't. Uncle Mike's and maybe Ox-Yoke at one time offered them in brass for Hawkens and in blued for Renegades and other TC models with blued furniture.
Measure your thimble diameter and look for a swivel of appropriate diameter that clamps onto the magazine tube of a modern rifle.
Try the partsguy1971 on eBay in the Black Powder section, his Dad owned the catalog company years ago CAINS muzzleloader parts that I would buy from back when now he sells hard to find parts, I just bought parts for my Cherokee from him