OK - I know this is S&W Forum - but I'm sure folks here appreciate nice Ruger's!! I have a near-new .45ACP cylinder for sale. Up front - this is an older large-frame cylinder - it is too large to fit into the frame window on my New Vaquero .45LC. But, it will fit large-frame .45LC frames, and the old/original Vaquero .45LC frames. It came from a circa-2005 Blackhawk .45/.45 that I have long since sold. I didn't ever fire this ACP cylinder, and I do not believe the original owner fired it. There is no 'bad side' of the cylinder - it looks the same as the photo, below, all the way around. There is a slight turn ring, but no dings, rust, scratches or damage anywhere. Asking $100 shipped - I have PayPal. I do not have a cardboard cylinder box or red felt bag that these cylinders came with years ago.
Edited to add: this will fit all older large-frame Blackhawks and Vaqueros - from circa-1963 until the new, smaller-frame .45's were introduced a few years ago.