.454's are pretty universal in that for the most part they'll fit most .44 caliber C&B revolvers where as there are a few that may not take the .451.
Speer & Hornady are 2 brands that have been around for a long time & both make a very good product, I've only used Hornady .457's "when some one want's to buy me a Birthday gift, don't they know I make my own
why not a subscription to Bowhunter or Muzzloader magazine
" Sorry, & they shoot quite well for me.
has the best prices around IMO on purchasing Cast Balls/Bullets.
I also like Track of the Wolf
for their reliability & service & they do carry Hornady Balls & Bullets.