Crunchy Frong said
"I don't think any one makes a clone (by my definition) with the firing pin on the hammer."
You had me 'til this statement. Are you sure you meant that? MOST Ubertis, Piettas and USFAs would meet your definition--unless I missed something, enitely possible. Most USFAs have slightly larger cylinders, but are otherwise pretty close.
If the OP just meant an "SAA like" gun in the broadest sense (size, general feel and overall appearance). I'd +1 the Ruger choice, which by the way--in terms of current and recent years' production--is the New Vaquero (cap N), not just "Vaquero," occasional special distributor-only runs of the old/original/large frame Vaquero notwithstanding.
Ruger tutorial:
Distinctions are not being made in this thread but "need" to be. It's true, Ruger itself--along with its dealers--inexplicably for the past two years has been calling in it's descriptive literture and ads all its current midframe fixed sights just "Vaquero," but they are more correctly "New Vaqueros" (big N) by definition since 2005 or so. And...not "new model Vaquero" as many call them (all Ruger SAs since 73 with the transfer bar are New Model Rugers...so the term just confuses and is not necessary, but most folks know what you mean anyway even if "improper" terminology. Still, maybe newER model, if you absolutely must say "model."
. Ideally, it's just "New Vaquero" and it says so on the frame (of .357s and .45s). If you say, "do you have a New Vaquero," and the vendor says "yes,"..ask what it says on the frame. (See the .44 Sp exception below).
One anomaly is the .44 Special--also inexplicably, it says just "Vaquero" on the frame, but be assured it's the midframe "New Vaquero." Otherwise, a gun marked just "Vaquero" is the large frame model, and btw, not needed for the .357, though some still like--but increasingly a minority. With either version, I'd get a 4-5/8" (5.5" absolute max) to keep the heft down and the balance "better," what with those relatively small holes, and especially being all steel like any gun with "Vaquero" in the name.
SO, if you see a NIB "Vaquero" advertised or at a store, it's a good bet these days it's the smaller ."midframe" New Vaquero. If the vendor doesn't know the distinction (more common than you'd think) ask what it says on the frame (regardless used or new), especially if .357 or .45. Voila. (Again, factory .44 Special is easy once you've got it down that ALL are the smaller midframes NVs, regardless what's on the frame).
Another reason--among the Rugers--to get the smaller, midframe New Vaquero is that it has an "reverse indexing pawl" which aligns the chambers "correctly"--like a Colt or SAA clone--for loading/emptying. The old/original/large "Vaquero" doesn't, but unless you're watchful instead over-travels, requiring you to move on to the next chamber. Earth shattering? Perhaps not, but an irritant to some, especially if speed is an issue. An aftermarket "free-spin" pawl eliminates this overtravel problem but as it's name suggests does not stop at any chamber at all on its own. A good or bad thing depending on your preference.
Both large and small (midframe) are great guns, but there are differences. Important to some, not others. Especially in 45, many prefer the larger Vaquero for its ability to digest virtually any load--including "hot," "magnum level,"Ruger only" loads. But, contrary to popular misconceptoon, the New Vaquero can safely shoot virtually any store-bought .45 load that's not designated "Ruger only.". Lastly, if you want a .44 Magnum -- it's easy, it come (came)only in the one size version, the large Vaquero.
Other distinctions:
New Vaqueros have thinner gripframes/backstraps and accompanying much slimmer factory stocks (panels). If too slim for you, the above is correctible for most by aftermarket/custom grips, most of which are not as slim as factory. The old/large Vaquero's overall profile, viewed from the side and back, is slightly different in addition to being "larger." Again, a difference important to some and not others...but grips are a very personal thing--especially on Rugers. Most folks are in one camp or the other when it comes to grips and especially gripframes. (On the Colts and Colt clones, mnot so much so--most folks eiter like or are neutral.) Gripframe swaps from one model to another are possible, just not super common. People just usually get the overall gun that suits them to begin with, and dial n new grips to adjust that aspect (if at all) to their liking.
Most[g] New Vaqueros have a relatively high, backswept hammer versus the old/original/large Vaquero's standard, more forward-oriented short spur (we've talking non Bisleys here). Exceptions--for new guns--are the Montado, a special NV model with short barrel and Super Blackhawk (SBH) profile hammer (but it's own distinctive checkering), and the relatively uncommon "SASS" NV models, which also come with the lower profile SBH hammer. People can always change hammers out of course, especially on Rugers a popular thing to do, so the above is not a hard and fast rule if buying used. Some like the standard (non Montado/non-SBH) hammer, many do not. Because of the above, relatively easy swaps, not a reason to not get a NV if you're one that doesnt. It's rare but occasionally you'll find an old/large Vaquero with a NV hammer swapped in, and slightly more common the other way around. SBH (and similar Montado) hammer swaps into other models are very popular.
Easy