rugerrat,,, it's nice to see you weren't upset at Mike's polite comments concerning terminology. What he says is all true. Please allow me to add to what he has said, especially considering your mentioning of seeing certain terminology online.
Old Model is a term used to describe Ruger SA's built prior to 1973. None of which are Bisleys. They are the ones w/o the safety transfer bar action. In 1973, Ruger introduced us to the safety transfer bar, and put on their guns, "New Model." As such, we call the pre-1973 guns Old Models since Ruger designated the later ones New Model. The original Vaqueros share the same frame size as the normal Blackhawks, and can handle the stouter "Ruger only" loads. The Vaquero was introduced in 1993, and as such, has the NM action parts. This is what your gun is. Most of us who collect call them "Original Vaqueros" to show the difference in the way Ruger marked the smaller framed "New Vaquero" models. Again, following what Ruger put on the guns. This way, we as collectors & parts people etc. can understand the difference between Old Model, New Model, Vaquero & New Vaquero.
I hope this makes things clearer for you. Sometimes some folks get upset at us when we try & offer polite discussion on terminology, and others do not care one way or the other. But it can be confusing when you start looking for parts, or trying to sell or buy a specific gun.