RE: 58 cal Hawken ?
You could check out the kits offered by Jim Chambers and Track of the Wolf. I dont recall exactly what they offer but if they dont have one I bet they could direct you to a source. If you cant find a hawken you like, a buddy of mine has an 1858 enfield reproduction made by euroarms that shoots roundballs as good as anybody would ever want. It will shoot them straight with heavy loads too. He hunts with .575 balls and 80 gr of fff. The mv is over 1500 fps. TVM offers guns built to order too. You might check with them if you dont want to fool with a kit. Or if you can find a hawken with a 1" or larger barrel you could rebarrel to 58. Good luck.