1853? - 3 band Enfield .577? "Musket" denoted smooth-bore of .75 to .80 calibre, normally. Rifled musket denotes a smoothbore musket that was returned to the maker and was rifled.

Bobby Hoyt could probably fix you up with most any type of rifled tube, if that is what you want.

I would have to decide, what would I do? Because no one I know of is making progressive depth rifling, aside from PH in the 70's and 80's, I'd likely have a .58 cobbled up with a .48" to 75" twist & with .010" to .012" deep grooves for patched round balls only.

The gun design, if the 1853 Enfield does not lend itself to heavy charges of powder, thus I'd likely not have ANY compulsion to using 'conical balls' in it.