1 wire alternators
Any one--wire alternator pretty much has to have the regulator internal, or at least a very small one bolted directly to the alternator. In the case of (for example) the older GM 12SI and similar, the only difference in the 3 and 1 wire setups is in fact the regulator, so you can convert any integral regulator GM by simply buying the proper regulator
But here's the thing. I see NO advantage at all to a "one wire."
A "one wire" complicates NHRA mandated trunk mount battery switching, where as with an external type or 3 wire, you can simply break the field circuit along with the battery
A "one wire" senses charging voltage AT THE ALTERNATOR instead of at the battery. This means if the charging wire is a little long and a little undersized (such as a factory Mopar wiring harness) the battery may very well be a little undercharged because of voltage drop in the charging harness.
Many "one wire" setups like the power masters use regulators which the average parts store is unlikely to carry, meaning, if you are on the road, etc, and one fails, you'll either have to carry a spare, or "hope you make it," on the battery
So my question to you is, "why?" And what are you working on? What is wrong with your setup now that you need to improve it?
The other uncool factoid about a "one wire" is something no one ever talks about. Let's say you were silly enough to run the battery dead, or pretty much so. Many people believe that alternators will not "self excite" but this is not so in the majority of cases, and I've DONE it.
If you have a stick, much of the time you can push start a car with a dead battery and get it running. It'll probably take about 4 guys to move it far enough and fast enough, but I've seen it done.
Of course if you have a Torqueflite new enough that it has no rear pump, this won't work