Just come to a shoot. That's the best way to get any and all questions answered.
We're cowboys and we are happy to loan stuff to a pard to let them try things out.
Just remember, this ain't IPSC or PPC!!
We take our time and have a lot of fun!
As to costs, most of us pick things up a bit at a time, so that's hard to tell and depends on whether you buy used or new as well as the make of the items you buy. A new SA Colt will set you back over $1000. but a Ruger Vaquero is about half that if you shop around.
Shotguns rifles and revolvers get loaned and are staged for new shooters all the time.
Cap & ball revolvers are good inexpensive revolvers to start with or any single action that may find its way onto the wire. (Many of us use Ruger Vaqueros)
Any double barrel that does not have ejectors or an 1897 Winchester pump or its Norinco clone or a Norinco 1887 lever action shotgun is period correct.
A lot of folks use Uberti rifles, clones of the 1860 Henry, the 1866 Yellow Boy and the 1873 Winchesters as well as Rossi and Winchester 92's and '94's in a pistol caliber.
There are some listed on the EOHC website as well, at 3w.eohc.ca that I have up for a Montreal pard who is getting out of CAS due to the drive he must make to participate.
The Single Action Shooting Society at 3w.sassnet.com has all the rules etc listed and can be a fun place for cowboys from all over the world.