TDS
Shiloh will discuss ROT with you, depending upon your needs. If you intend to hunt, it will be slower; if for BPCR silhouette using 550 gr bullets, it will be faster. I don't know the policy of C.Sharps - just ask them.
I had a C.Sharps '75 'Business Rifle' in 45-70. It's one of those guns I should have kept .... :>( Shot better than my current Shiloh BR. Had the C.Sharps tang and globe front. I swapped it off because of it's straight pistol grip. Replacing it with a PG/cheekpiece stock would have been smarter. A pal has one so set up and he won't part with it. He likes the lighter hammer fall of the '75 action.
You will be waiting a few years if you order a Shiloh unless they've had a cancellation; C.Sharps may have one ready to go. Again - give them both a call. Buying from a dealer/speculator will get you what you want right now; at a premium price. You pays you money - you takes you choice.
Shiloh's warranty is off if you shoot smokeless in a calibre other than one intended for smokeless, like the 30-40 Krag. I've never heard of a '74 action coming apart, but nothing is fool proof in the hands of a fool. Frankly, shooting anything other than BP in a buffalo rifle is almost an abomination. Cleaning the brass is a PITA, but it's part of the game and you get that big voice ''Boom!" and all the smoke ..... Otherwise, what's the point?
There are all kinds of good sights out there right now. How much money do you want to spend? Look at a few and shoot them if possible.