All of the components of this ensemble have William Shatner tags, including a large Western Costume tag inside the jacket. The tag's number, combined with the jacket's color and details indicate that this was originally made for "Wrath of Khan" and modified for later use by other actors.
Shatner wore this style of uniform beginning with Star Trek II: The Wrath of Khan through Star Trek: Generations. There's only one template for captains in Star Trek – William Shatner's James T. Kirk. And then they broke the mold.
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Wrath of Dhan Maroons