The only Major car hire option in Tralee is Enterprise. Their office is about 1,000 feet from the train station. https://www.enterprise.ie/en/car-hire/locations/ireland/tralee-i124.html?mcid=yext:245709
However, the Dublin to Tralee train also stops FIRST in Killarney (Budget and Enterprise) and then, nearby the Kerry Airport: http://kerryairport.ie/website/transport/car_hire/
There are also options located in Galway, so either route would be 'do-able'.
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Bob
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