ID this alternator?

Read through the posts here
Identifying Chrysler Alternators (1960-1976)

If this is a beautiful restoration or original car then you may want an alternator that matches that look, as well as functions properly.
There's just a couple shops that can do that. And you can use a cheap substitute in the meantime.

One caveat. The ID thread only shows the standard alternators. If the car was equiped with Chrysler Heavy Duty or a Leece Neville alternator, it may have three wires connecting to the regulator. That would be one clue.