Yes, the local auto parts store to me sells kits for them that include
the regulator, the brushes and the bearing.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
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yes it is replaceable as a separate part, and it is not terribly
difficult.  PRobably won't be able to find one at your FLAPS but Summit,
Jeg's etc. will sell them to you (search for "one wire conversion kit" -
the difference is the regulator.)  However, were it my car, I'd probably
 just get the standard Delco regulator and run it as a three wire.  If
you don't have an idiot light, Speedway sells a plug with a diode in it
to keep it happy.  As a three wire unit you get remote voltage sensing
and instant turn on, with the one wire it only senses voltage at the
output terminal and you may have to rev the engine a little bit to get
the alternator to turn on.  I'm running the regular Delco 10SI with a
Speedway plug/harness in my Stude and it works fine.

good luck,

nate