Geralt's first real armor is a studded leather jacket given to him by Vesemir towards the end of the prologue. It can later be upgraded to the Excellent leather jacket. It can only be sold to human blacksmiths. This jacket can be purchased from Mael on Rhundurin Square in Vergen during Chapter II.
Studded leather jacket, Witcher Wiki
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Studded leather jacket, Witcher Wiki
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